Landrover don't make their own units, so it could well be a rebadged VDO unit. It's worth a bit of research - look for photos of the original, or look closely on your own for a makers mark.

They are a tapered thread, probably something like BSPT. I find hitting them with a suitable sized hammer before putting a spanner on them helps. Not sure of the size - I seem to remember it was maybe 11mm?

I fitted a Boomslang together with Wipac crystal lenses - a big improvement. I'd say the light output is as good as many modern cars, but not stupidly dazzling as many are. It's certainly not without flaws - the headlamp bowls had to be cut to allow the headlamp plugs through. I tried removing...

If you're buying new discs, have a look at the grooved/drilled options. IIRC they weren't much more expensive than the standard. I can't say for certain how much better than new standard discs they will be, but they certainly look good when you're "down there" lol.

Your last comment suggests you have found the problem. To be sure you need to thoroughly clean the engine and look for the oily bits after a run.

As you suspect, the early stuff - callipers, master cylinders and servo are different. I had difficulty getting hold of a pair of fronts for my 1985 90" a few year ago - and they were expensive when I finally succeeded! You might need to hubs to suit, I'll be interested to see if the newer...

You just about got away with that. I've had one go on a dual carriageway - you won't forget the noise, even if it doesn't cause any damage! As you say, at over 200k, it's time for a new prop - they have lasted well.

Sender is resistance to earth as mentioned. 14.5v doesn't sound right though, i believe this should be a regulated voltage. Maybe the wrong feed to the gauges.

In my experience it's definitely worth budgeting for a replacement clutch and springs/shocks. These are much easier to change while the body is off. I went for a Richard's Chassis, supplied and fitted by Trevor Cuthbert Landrovers. Highly recommended, but not handy for you.

Fitted a slickshift. It definitely does reduce the throw required to change gear quite a bit. Adjusting the bias springs correctly removes almost all the wobble/slack too - this bit would help even without fitting the kit and is an easy job.

Sounds like a good idea. The rating for the existing in line fuses should already include a safety margin, but I would always buy cable of more than the capacity required - this gives a safety margin, allows you to add more accessories in future and also reduces voltage drop between the battery...

Here are a few photos of my 1985 90" setup. The standard flaps are from Rimmers, the genuine ones are more expensive, but last longer in my experience - as long as you're not doing much off roading. The other two bits are cut from 3mm rubber sheet. Really cheap and easy to cut - you can...

I've seen a custom exhaust they made for a friends V8 - beautiful welds.

Just a thought - it's worth clamping the rear flexi to see if you get a bit of pressure at the pedal, it will help locate the problem to front/rear at least. If it makes no difference, I would remove the servo and pull the master piston to check that the seals are ok - even if it is new.

Yes, I did convert a couple - there is enough meat on the supplied adapters. However I found an M16x1 die was pricey/hard to get - PM me your address and I'll post you an adapter I made out of the set.

I did a write up on this very topic a while back: https://www.landyzone.co.uk/land-rover/the-200tdi-temperature-sender-threads-thread.311325/#post-3924847

The senders that come with the durite gauge are something like 1/8th NPTF, so you need an adapter. There are packs of adapters available, but I couldn't find one that fitted - so made my own. I should have a spare if you are stuck.

Early disco 200tdi had a m16 x 1 thread on the temperature sensor. Later ones seem to be m16 x 1.5. The early fine thread adapters can be difficult to get, i bought a die and made my own.

I'm probably too late LOL, but they're not self tappers - I think they're called a spire nut or similar and screw into an insert. For my 10p worth, while you have it stripped down that much, I'd replace as much of the bulkhead as possible. Any rot left will just get worse and you'll have to go...

I think that's just for connecting accessories - additional gauges, radio and the like. Pretty sure my 1985 90" has one too. Older radios sometimes needed both switched and permanent live, and even a feed from the lighting circuit so the little display lit up when you turned the lights on...