I like mine stock looking (up to a point, gotta have better wheels/tires and exhaust). The attached recent pic looks like a stock '70 318 car except for wheels/tires and exhaust... but packs a 496 and 5 speed.

I too started with the frame/chassis/suspension... and brakes. Good move to stiffen up the frame with frame connectors first. There are several choices but US Cartool sounds like a good one. It takes some time with a cutter and MIG to get any of these these right.

A far as suspension, a modded T bar setup has a number of advantages including lower un-sprung weight, service parts availability and all weather capability... not to mention great performance. I won't run mine in the winter salt but do run it X country with whatever that brings including rain, T storms and cross wind.

As far as brakes, I consider some form of front disc minimum for use today. They can be mid-70's OE or better but 4 wheel drums just are not safe if the guy in front has discs or if you are running at speed and need to stop more than once.

Good luck!