'86 B2000 Exhaust Manifold Stud specs
 

I just bought a very used B2000. There is a Pacesetter-style header on it but a couple of the studs/bolts attaching the header to the cylinder head are broken. The rest are hex-head bolts which also doesn't seem like the right thing.

Can anyone tell me the fastener type, length, and thread size that should be used here? I'll probably just pull one (if I can) and take it to O'Reilly to check, but since I'll be poking around here I thought this should be where I start.