Hey Guy you've definitely found the right place, welcome!
Best advice I can give, K.I.S.S.
Look over Greg Welds Track car and get to know who Mike Maier is. Both of these cars are simple, no crazy frames or exotic parts. If you're planning on competing, the cage as well as some basic SFC's are all you'll need to stiffen up the chassis.
I looked over all the cars at the Historics this year as well as the Shelby event at Thunderhill. I was surprised on how basic these cars are set up and still perform as well as they do. Subframe connectors, panhard bar, and leafs are the norm. The front suspension was all based around OEM, some had coil overs and aftermarket control arms others had reinforced arms and dropped springs. Easy cheesy!
Cool link on the bracing, I hadn't seen that before.
Dan