Greg,
I am not as familiar with the GMC's, but does your engine have more than a standard amount of head studs?
Second thing. Correct me if I am wrong guy's. Doesn't the GMC use the same timing set a 235/261/250/292? If So 12Bolt has adjustable timing sets in stock. Oh wait, I see you want STEEL cam gear also. Those are in the works.

Inliner Member 1716
65 Chevelle Wagon and 41 Hudson Pickup
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