First of all, FORGET the '302's. Unless heavily worked (ported) they will not do one single thing in your quest for improved power.
Moving on, I would be prepared to spend some $$$$. I would bolt a pair of these on.
'915 Ported (243 cfm @ .450") bronze liners down to 11/32" 2.02/1.60 S.S. valves, milled to 59 cc, milled intake face to correct, machined guides for lift and positive metal clad Viton seals, etc.... J.Rob