on wiring:
i specialize in that. do quite a few full custom hharnesses a year.
ive used all major manufacturers except isis.
the thing with painless verses similar kits, is their wire has more strands of smaller diameter, and their insulation is tougher and more flexible. they also include some wires that arent included in other kits, like ground wires, etc. very nice quality, but due to their fuseblock design, you have liited routing options and mounting options. little more cumbersome to work with than others, but better quality.
with your build, and they way that you seem to think, as well as the style you seem to be going after, id expect you to want to do a fully hidden wiring setup. best kit for that is a ron francis kit, as YOU make all the connections to the fuse bblock wire by wire, circuit by circuit. much easier kit to "tuck". only problem is their fuse panel is HUGE. no problem if you want to mount it in the trunk, but under the dash of an a-body, its going to be pretty tight.
im making a WAG on your wiring harness preferences, as im not one of the hemi family, so im not privilege to the top secret planning sessions.
if youre looking for a guy to do wiring, or need more suggestions, ask away.
Michael