I also spoke at length with Jerry Sackett, owner of Pantera International Motorsports in SoCal (he rebuilt my engine/trans/cooling system. He pointed out that the stress ultimately finds itself along the inner aspects of the rocker panels, thus allowing for the twisting in the body. Soooo …I followed his advice and had supports built.
I made paper patterns of the inner rockers, then cut cardboard pieces to outline the contour of each side. I could a local Metal/machine shop here in Jax, FL to manufacture the braces for me at a cost of $150 each.