360 build advice for my '70 dart swinger

Ok, cool, I would definitely like to change the gears to a lower ratio for sure once im there after a 500 mile trip, and I could pt the 3.23 gears in it that I have laying in the back for the trip down if I had to...Once I'm in town, I'd like to stay with 3.55's for sure. Which specific torque converter would you recommend for this build? Also back to this dual quad, dual plane intake setup...would that give me more power all around, and give me better high rpm flow compared to the single 4 barrel carb setup? I have a friend who has a 327 chevy motor thats on pump gas...that thing has dual quads, not on a high-rise intake, and it is fast! By the way, whats the specs on your 71 swinger JoeDust451? Just wondering..
Thank you,
-ANTHONY