I want to upgrade my cam and i was wondering what needed to be done to the cylinder head to install guide plates on them. Do the stock studs come pressed in or are they screw in. Can it be done with the cylinder head still on the car. Thank You.

 

They are screwed in...and yes it can be done with the head still on the car but it's a bit of a bitch to do....I did mine with the heads still on and it wasn't fine...I suggest a nice long cheater pipe for the extra leverage(sp?)...

 

The usual Comp Crane or the like do not fit well atall, you will have valvetip not covered laterally.
The GMPP guideplates fit better but still not quite right and they seem prone to wear.
I recently switched the Isky adjustable guideplates, even on a b-body they were a PITA to put in with the motor in the car, probably be a nightmare with an f-body.

I would suggest jumping right to 7/16 studs and rockers long as you will be buying parts. Always cheapest to do things once.

 

you don't need guide plates if you get rockers that are Self Aligning(SA)