It will be an LT95.
You might need to get different propshafts suit the length, as the transfer box outputs will be in a different place to your current set up.
The tunnel cover may need some modifications, but these will likely be minor... don't forget the get the vacuum switch from the donor vehicle as this is needed to operate the centre diff and can be expensive to find.
The 4 speed box will probably be a bit noisier than your current 5 speed, but they are *very* tough.
Get as much of the exhaust system as you can from the RR... you will need the downpipes and y-pipe as a minimum, the rest you can make up from bits of the existing system and the RR system.
Best of luck :-)