Man, you guys are making my day. I've been doing some research, and it appears that all the braking components are the same, aside from the front rotors and rear chassis to axle brake hose. Considering I've replaced everything except the hoses, that's good news.
It even appears the new front springs under the 2wd are also the same as 4wd.

The floor pan part I was aware of. I haven't yet decided whether to use self tapping bolts, or go borrow my buddies "Rev-nut" tool that installs a threaded sleeve, and locks it in place like a pop-rivet.

On another note, it appears like I need to add another line to my sig. Picking up a 95 Mazda B2300 (Ford Ranger) for $700. I expect it to be my son's daily driver as soon as it gets the once over.