I just did this gasket replacement on my '84 245 Turbo, using the NAPA supplied gasket, which seemed thicker than the one that was in there. I noted that no sealant was used on the old gasket, which also blew out at #4. I just laid the new gasket on the studs and spread a bit of gasket shellac(habit)over it before bolting it up.
From not being disturbed for such a long time, the manifold was stuck onto the frontmost stud. Repeated soaking with penetrant and wiggling didn't work, and tapping on the stud did nothing. My B21FT manifold did have two semicircular pry points on the underside at the front and back, and a six inch extension wedged in there and pried downward finally coaxed it loose, without scratching the soft aluminum seal surface.