Before bolting them on, lay the head gaskets on both the head and block to make sure there's no blocked passages ( other the the front one) As for pushrods, you'll need ones for a 78-84 302 ( pedestal rockers and flat tappet cam) I'd also do a clean up on them with a die grinder before using them, grind the thermactor bumps down flush in the exhaust ports and remove any other sharp edges in the chambers and ports. If you're gonna have them reworked, I'd also blend the bowls too, under the valves.
I was going to do a gasket match today and smooth out the, sticking any rotating metal grinding thing inside the bowls scares me. be my luck I will hit something that should not be ground on.
Just steer clear of the seats. You'll do fine. I got faith in ya, Monkey There's usually some rough stuff under the valves where the tooling for the seats was shoved down too far. When doing the chambers, get a couple of old valves to use as seat protecters when grinding.
I did the exhaust ports on one head today. My lord thats a lot of grinding. the thermactors were the easy part. Now I am trying to get it all level and smooth.
I did not find much under the valves. a few raised spots that I ground down.
Yea, there is a lot of grinding, and the results can't be measured, unless you dynoed it before the work, but the piece of mind that all that restriction is gone is worth the trouble. I also raised the port roofs on the set I did and opened the sides by a good 1/4" to match the headers better. I did nothing to the port floor, other than polishing.
If anything replace them with a set of one piece retainers, but as to when? If you're planning on winding it up to 6000+ regualrly, yea, I'd change em now.