I have a set of LT1/SBC 7/16" Rocker Locks (Poly Locks) that use the allen head. They are i n great condition and have only been used for about 12,000 Miles on my LT1, they are for any SBC/LT1 but would work with any engine with 7/16" studs I believe.
FIT STOCK LT1 HEADS or SBC HEADS
Asking $30 picked up or buyer add shipping.
214 686 9375 (Call or text) or Email Me MIKE
This is what they look like.