Half shafts 30 spline readily available to any length 300m circa £110 ea from the states. Detroit locker 30 spline centres again cheap and readily available. The worst part was finding a drive flange to modify/make fit the hub, I was give a name of a dodge truck used on alot of the UK US run air bases as a starting point they had huge flanges I could spin down and re drill.
My bro reminded me about the 2 Humvee genuine military h1 portal boxes he has under his bench then he showed me a picture of the Sierra sized diff! It looks puny!!