So I snagged a pair of X heads...

Good info, thanks guys! I think these heads will be a huge help for a budget small block build :)

For the pushrods, is this for crazy cams or just roller cams in general will require head mods?

Last, all the valves are here except one exhaust valve. Obviously I'll need new springs, retainers, etc but should I keep the valves if they're good and just replace the one missing one, or is there newer valves that perform better?

Last - I've been saving the adjustable rockers from my 273 in case I need them. Any reason for me to use them on this engine or are non-adjustable ok? I'd like roller rockers but the price is so high for Mopar, not sure they're the best bang for the buck?

It was more because of the type of roller used. I used a hyd roller and with the hyd roller lifters it put the angle of the Pushrod at too far for my liking and had strong possibility of cracking and reducing the strength.
Pushrod
http://www.forabodiesonly.com/mopar/showthread.php?t=131950

Aluminum heads
http://www.forabodiesonly.com/mopar/showthread.php?t=132009

Pictures can be seen about what issues I had.
It is completely worth it to bite the bullet and use roller rockers because roller cams use higher spring pressure. I like my Comp Pro Mags :twisted: