What tools do I need to replace transmission in my GMC 4L60E. 2005

You don't specify the car or truck this will be done for, I assume it's for a truck. (For some cars the subframe needs to come out, which also means pulling suspension parts.) You'll likely find worn engine/tranny mounts, worn cross member mounts, worn CV joints, leaky rear main seals, axle seals, etc. I've pulled trannys in the past and then find myself ordering various mounts and bushings and having to wait days for those parts to come in, so be prepared. For tools, you'll need a full set of sockets and wrenches (open and box). You'll need jacks and jack stands or a lift, a tranny lift is a huge help. You may need to remove the exhaust crossover, and on old rusty vehicle that can be a task. For suspension work you may need a spring compressor. A torque wrench. A breaker bar. A thesaurus of curse words. You'll want to spray bolts with a penetrating oil a day before you start wrenching. You'll need to be able to check your ATF fill level which may require a special tool if yours doesn't have a dipstick. A good repair manual will have all the steps and tools needed for the swap. It will also give you torque settings. If replacement tranny is from another year you may find yourself having to deal with computer reflashing. 4L60E is a big tranny so having a tranny jack is huge help.

If you need a list of tools this job is beyond your capabilities.