Harvesting the carcass

It appears I'll be picking up a body donor for my '75 Valiant. I'd like to pull the rockers, wheel houses, floors, etc. as 'factory type' replacement panels.

Is it better, or is it even possible, to just drill all the spot welds and pull a panel like turning back the clock? Or should I invest in a plasma cutter and carve it apart?

I'm kind of against the plasma cutter, because maybe I'll want the adjacent panel. Is it possible to pull two or three pieces together and splice 'em in to the parent vehicle as a factory weldment?

I'm new to this. Any advice is appreciated.