[screamingchief]

First question is what's the advantage to using screw-in studs over press in besides the obvious of using aftermarket studs? Are both adjustable?

The stock "pressed in" studs are weak and unreliable,they will either pull out or break at the single worst moment they possibly could,likely when your miles away from a possible solution to that issue...

The fact that they can be made adjustable with a set of the correct poly-locks only decreases that inheirant drawback by the slightest amount.

Besides,you state you plan on using 6X heads for this,those are all screw-in-stud heads anyways,so why sweat that detail,just unscrew the stock "bottleneck" studs and replace with a "straight" 7/16" screw-in-stud and presto,,,adjustable valvetrain,,,no muss,,,no fuss...

Good cams for a combo like you mentioned???

Plenty out there,and everybody has a favorite one,so I'd hafta defer that recommendation to others,my choices would'nt likely be those many would agree with.

I'd likely advise you read the archives some and ask that question in another thread afterwards.

HTH.