Anything I should know about installing Vortec heads?

Mid to late 90's Chevy/GM Trucks including Suburbans, Tahoes, Yukons have them.

 

I have pro comp alum vortec heads with the 4 bolt style valve covers, an edelbrock proformer vortec intake, on my '81 350 I have the original stamped rockers on it but they rub on the inside of the valve covers what can be done about this? also I've read alot about the water circulation problems but Im unsure how to fix it I don't have a water outlet on the rear of the intake everyone I know of that builds motors are still using the old style heads so they don't have alot of information on vortecs

 

if your using stock vortec head bolts they do not torque the same they are torque to yeild

 

hate to ask but where could I find those cool looking Studebaker valve covers?