Here is a screw in stud head (notice the rocker stud location is smooth)
http://www.ausfordparts.com/ebay/2va.../2valloy_6.jpg

These are pedestal Stud heads (notice the groove where the stud screws in)
http://www.ausfordparts.com/ebay/A35...ages/head1.jpg

Press in studs are basically a variation of the screw in stud except they are pressed into the head (no groove).

 

so all stock ford heads are pedestal? does this mean that http://store.summitracing.com/partde...N&autoview=sku you cant adjust? whats the whole deal with this kinda stuff? i always thought that you could adjust all rocker arms?

seems like the stock chevy stuff is press in stud mount cause you can adjust pretty well?

 

Once torqued the pushrods should still be able to be rotated. If they will not rotate, the shims will have to be used. Begin with the thinnest shim and retorque and repeat as necessary until the pushrods can be rotated without any end play.