Easy, engine, box transfer, rad intercooler out of Disco, cut off engine mounts, remove efi plus gearbox rad etc. weld in engine mounts, engine and box in connect up steering pump etc with Disco parts, use Disco exhaust jobs a good un. :lol: :lol:
I have a 200tdi in my 82 RR that was even easier as all the floor comes out, didn't take very long atall, biggest issue was cutting and shutting a gerbox tunnel for the later 5 speed box, but yours already has that sorted. The V8 box won't bolt up to the 200tdi so use the Disco one which fits fine.