I have bitten the bullet and ordered my new chassis today to finally carry out the rebuild on the dead 109 I bought a few years ago to rebuild.
Now I am doubting myself on the spec I ordered after reading the various links etc on power steering. this is mainly because on the forum and t'interweb there seems to be some contradictions.
So three questions have I.
1. if I fit power steering should I have ordered the welded damper bracket or not?
2. Can I fit power steering if I have the engine compartment battery option as original?
3. have specced the welded on P38 bracket assuming there are no other chassis alterations needed, is this correct?
The reason I can find any of this info online is that mine is a 2.6L 6 pot and everything I can find is for the 4 pots.
I have just had confirmation of my spec through from Richards and will call them tomorrow (I had put some of this on the order form to be confirmed but it just went through) but any advice on fitting P38 power steering to a 6 pot would be welcome.
I am assuming I can fit a pump on the top of the engine where the air pump was?

Watch this:

Looks OK.

I did watch that but there is no steering damper shown and I have seen mention that power steering will not fit if the battery is in the engine compartment?

I don't get the damper issue; why fit a hydrualic cylinder with a restriction that is fighting against the hydraulics in the PAS system? It should be possible to set the PAS up to damp itself.
The things I took away from that video were, 1 the steering will be too light and you need to signficantly change the geomentry to make it safe to drive, and 2 the power steering is being fitted to a vehicle with non-servo brakes which to my mind makes no sense, I would power assist the brakes before the steering.
When you look at the "resto-mods" builds they always uprate the suspension when they change the steering and brakes, because increasing the ability to turn changes the demands on the suspension dampers and spring rates.

I was not sure whether a damper would be required or not, my understanding was that it was reduce bump steer over rough ground but if it is not needed with power steering then good, a bit of cash saved.
Looking through t'interweb it seems that the brackets Richard will fit will allow the Steve Parker kit to bolt straight on, however the last question about battery boxes may be the killer. At the moment the battery box is not a problem as the steering wheel goes through a steering box bolted to the bulkhead. All the conversion info I have found seems to indicated that a defender column needs to be fitted directly driving the P38 steering box which would foul the battery tray. Can the P38 box not be mated up to the existing steering system or do you need to change the column?
If I need to change the column and steering wheel then that is a change too much for me, I don't mind some plumbing under the bonnet but I want the dash to stay the same with the old series steering wheel.
I already have a servo on the brakes fitted as standard.
I was only planning for power steering for both the missus and for me in maybe 15-20 years time. Thought I may as well fit it when rebuilding the vehicle now.

Having spoken to Steve Parkers and carried out more research it seems that I will not be fitting power steering after all. I would have to move the battery in the engine compartment to under the seat but more importantly would have to remove the steering wheel and column and alter the bulkhead to fit a defender steering wheel. While I am not a rivet counter I don't want to do this.
So it looks like monday I will need to alter my chassis order to remove the P38 bracket and leave the damper bracket.
As an aside, I know it is a popular mod but what general proportion of series landrovers have power steering conversions fitted? 10%, 50% 90%, just how common a mod is it?

Your question re what % is a good one and I honestly have no idea. As someone who goes to quite a few vehicle rallies what has suprised me is how many series have front discs, perhaps 25% at some meets. I drive my LWB with the really heavy Perkins pretty much evey day and I live in a town. I really don't find any problem with the standard steering, that's not to say its like a modern car, but technique and some planning overcome 99% of the issues. The one big concession is avoiding parrallel parking in tight spaces, I plan ahead and find bigger car parks. This is not a problem as we have a camper roof and so we have to check the hights anyway. My other car is a power steered Merc. On the move I would say the Series is lighter and its certaily more balanced, the problem with the Series is the play but I spent yesterday shimming the steering box and its made a huge difference. I'm 65 and average build. I think you have made the right choice, if the steering does become an issue in 15 years look at the electrical conversions or the Heystee as this bolts on with no mods. I don't think the P38 system is a particulary good one, OK but nothing special so there's no rush.

I was about to suggest the Heystee system, although I have never found anybody that has fitted it to find out how well it works.

I used to have a 90 years ago and it was non power so I know what I am getting into. The intention is to rebuild all the underpinnings and mechanics of the 109 but not to really touch the outside other than touch up and removing a few dents. I want it to look like a working landrover as it will be used as a kind of utility truck and I don't want to have to be worrying about getting it dirty

If I look back on the past 5 years of slow but continous improvements to my 109 that I have converted to a camper it is now a much nicer vehicle to drive and on the whole very reliable. There has been a lot of necessary work, an engine and gear box rebuild and chassis welding, but for use I would say the things that made it easier and safer to drive are (in no particular order)
Re-wiring will all earth returns, more fuses and the addtion of intermiitent wipers, wash wipe, hazards, better interior lights, rear fog, high level brake lights. We also have rear strobe lights in case we have to stop as we use a "smart motorway" and its is clear other driver do not see the standard rear lights on a series.
A bigger brake servo (90/110) and modern high friction linings. The brakes (drum) are now on a par with a modern vehicle. I think this is the biggest safety improvement
Spending time setting up the steering and brakes to work as they should. This is beyond maintence, its not accepting a poor set up and lots of small adjustments.
6 1/2" rims with modern all-terrain tyres. Grip and handling are much better, getting the brakes working well exposed the weakness of narrow tyres.
The overdrive, money well spent. Better economy, less noise and better cruising. Shfting the cruising speed from just slower than trucks to just faster was worth the cost on its own.
Sound proofing, we typically drive 100-200 miles on a camping trip and cutting noise really reduces the fatigue.
If I look back on longer trips and what causes tiredness its not the lack of power steering, its been noise, brake effort and steering play..Time spent getting rid of those is worth it.
A power steering conversion is not on my wish list, but front discs were until I found how good i could get the drums, now I don't think it would be an improvement
Best improvment? Toilet and sink, especially since the lockdown! Makes us fully independent.

Funnily enough Richards have come back on my query about dampers this morning and said their "technical Department" says that the damper should still be fitted with P38 box. This directly contradicts what Parkers and my own research says.
Its a moot point as I have now instructed them to delete the P38 bracket from the order anyway but does show some inconsistency

I used to design hydraulic systems many years ago, for the most part they are inhearntly damped if the system is sized right. With hydrualic power steering the PAS pump is putting energy in and some of it is getting used in heating the damper. Its different with a manual system as the damper is protecting the driver from shocks but the hydraulics in the PAS system are already doing that, so I agree with your assessment.