i was wondering if the LT4/ZZ4 spring kit would work in 041 heads without any machining. they're 1.32" OD.

also, would it be safe to use those springs and a comp XE264HR cam with press in studs for a while?

 

I've had those springs (12495494) springs, and they do require head machining.

As for the studs and that cam, with any spring that's adequate to the task of controlling a valve on that lobe, you're risking pulling a stud. At a minimum, you should pin the studs. If you're going to do all that drilling and pinning, it's almost as easy to pull the studs and install screw-in repair studs as insurance.