Making progress... slowly...many hours but lots of thinking book ended by a little work lol.. getting close now but still have to prep are under cowl grill before it is closed to me forever again.
I formed a drip rail on the upper lip of where the firewall makes the cowl, so now I won't need the big cowl seal across the top to clean it up a bit. Going to have to clearance the hood inner structure for that possibly, but I was going to have to modify the inner anyway for carb clearance so....
Put a small gusset out from the firewall to the inner fender on the pass side inner rear fender for some added strength. Since this side will have several holes for exhaust and it is a little more compromised than the drivers firewall because the driver's side has the reinforcement plates for brakes etc. It is naturally much more rigid on the drivers side from factory.