There is a series of videos here, ok it's a Disco but it's essentially the same.

Which bushes did you use in the end? Yes brute force is the answer, on the upside along as you greased all the bolts it will come apart easy enough next time.

Fuel pressure gauge connected at the fuel pressure regulator? Under a certain voltage it won't start, apparently.

No I think they are spring loaded so not really free an easy to turn. In fact if it doesn't turn at all maybe the locking tab has been removed and it's locked in position.

https://www.ebay.co.uk/itm/235127935875 Buy the right one as they are not all the same. If you are confident the white wire is at fault could you not energies the relay with 12v just to test it? Then run a replacement wire from the relevant terminal on the ignition switch, to the relay, to test...

I am no electrician but sounds like, from your description you should get a live, white, when you turn the ignition to crank position. This energies the relay, circuit made by the earth wire, and let's current flow to the starter. Warning: I could be talking **** but it sounds good to me!

https://lrd-track.co.uk/products/fuse-box-to-battery-live-cable-relocation-loom If you are changing it for no reason whatsoever then maybe consider buying that, maybe.

Richards chassis I think. Reuse what you can as many aftermarket parts are poor.

Coil?

It's a Defender, that's for sure. I will guess at a TD5.

It can't be your last picture as that suggests you live cable goes straight to earth.

It's on the bottom of the pump in the plastic housing. If you have oil in the ecu then change the injector wire loom.

Looks tidy, what are your plans with it?

Is there not a technical drawing with all the measurements in the workshop manual?

2004 onwards according to Google.

https://www.lrparts.net/nahtddeftop-top-mounted-rear-gas-strut-nakatanenga-branded-for-land-rover-defender.html

I would be welding the chassis up first if I was you.

The more you pay and thicker it is the better it is, maybe! I don't think the difference between the makes is significant, more like we THINK it's better because it's more expensive so must be better. Up to you how much money you want to spend.

They all get stolen from a price of crap farmers truck to a blinged up Khan special. Puma bonnets and door as all the other ones have rusted out by now..