Blew a head gasket on rebuilt 383.

[Hammond68]

5000-6000 on it. I bought it of an older man. He may have used his own torque sequence, thought he didn't need a torque wrench, re used bolts who knows.
Anyhow, going vortec 062 now. Compression will be 10.47 to 1.64 cc chamber on on flat tops with 5 cc valve relief. Pistons are .025 in the hole. Comp 280 magnum cam. Comp cams recommend 9.3 to 10.8. Think I'm going to high?
Yes, I know I'll need an intake. Any advice would of course be appreciated. You guys are great,every time I need help spending my money y'all come running.