Are you running studs instead of head bolts on that rig? I'd definitely recommend getting a gasket made from .090" thick solid copper for it. Machine a 1/16" wide groove .030" deep in the block around all the cylinders, and form a ring of .060" stainless steel safety wire to fit the groove, with a very snug butt joint where the ends meet. As the studs are torqued, the wire will imbed itself into the soft copper and seal the cylinder pressure much better than any regular head gasket can. Use Permatex Super 300 brush-on sealer on both sides of the copper to seal the coolant.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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