SCORE! I predict that you'll love that body, I've had a fistful of old bodies and they all are he** for stout! Looks like you're on the right track with the transplant..rear sump, good..PS, good.....4 speed, good.....3 BBL....now THAT'S old school! Yes, if you use a front plate, it mounts to the water pump/timing cover bolts. Summit or Jegs sells an aluminum unit that should work great for your power level, if not, a 1/4" or 1/2" piece of 6061 T-6 aluminum is what you need. Looks like your fabrication skills are up to the task. Do alot of careful measuring and use the water pump gasket as a bolt pattern template, it's not too hard, I've made a bunch or front and mid plates over the years. Sounds like you're going to mix a little old school with some 60's ideas.......NICE! Keep us posted, I'm sure there are alot of people on here that will cream their shorts over this build! Good luck and don't be afraid to ask alot of questions!
Rob Hawes-Anchorage Rod Works-Anchorage, Alaska