1. Get an 8" from a pinto, bobcat or mustang II, and no on the tranny (and only a maybe the driveshaft).
2. I have gotten a few different brands of the plastic paint, but none seem to work well.
3. Here or ebay.
There are many people out there selling mustang II v8 parts, and they will advertize that the parts will fit in a pinto and make a v8 install easy; Don't belive all of it, some will, some won't, do your own research.
Bill