Need advice on changing clutch

I have a 1992 4x4 1500 that needs the clutch changed out on the manual tranny. My buddy is here that does alot of work on muscle cars but not much on trucks. He's changed many GM clutches but never one on a 4x4.

The question is:
Do we need to take both cross-members out and the exhaust cross-over out to change it or can we just slide the tranny and transfer case back and do the work with it still up in the truck.

Some fast advice would be greatly appreciated.

Thanks,
Fish