For all out cheap you can't beat an original TQ intake from 71 through early 80's. Be aware you will need different or modified kickdown linkage for your automatic transmission when switching from a 2 barrel to a 4 barrel. Use a 340 throttle cable bracket. Have to agree with post #8 above on carb choice. QJ is a close second but takes more work and know how. If you can find a good early small block (340 or 360) TQ with ported vacuum for the vacuum advance on the distributor it would work well, as is. I'd skip the headers and just run dual exhaust, since your exhaust manifolds are decent, just make sure your exhaust control valve is open or removed. If you would rather go new, I also hear very good things about the Edelbrock AVS2 and a Holley Street Demon, Although I personally have not tried them.