You've got several options with stock manifolds from 305 engines. Virtually all small block exhaust manifolds fit, you don't have to stick to ones for a 350. Try a quick trip through the local salvage yard, and I'll bet you find something suitable. Good call on NOT using headers. All they do is increase underhood temps, leak, and burn plug wires. I believe some of the Camaros used rear-exit manifolds. I used them on round track claimer engines when headers were not allowed, and we won lots of races with them.
Jerry
