I think the whole point is that you don't have to disassemble much of anything as long as you replace with the metal pan. I think you just have to remove the metal guard, then remove the bolts holding the plastic pan on, drop it as much as possible, cut the plastic neck with a small saw or something similar and yank it all out. Metal pan doesn't have the plastic neck, so you can install it without having to drop the exhaust.

 

I remove the t case support to make the job cleaner and make it easier to access the rear bolts, but it's not necessary.