Advice on head clearance

[Pete Fl/Wi]

1950 Merc engine.080 over, L100 cam, topline adjustable lifters set at 16 intake and exhaust, Egge cast pistons, copper gasket.Edelbrock 1115 heads. Using clay no problem over valves. Pistons tightest spot is center of pistons .065. Not to full torque but snug. Measured on distributor side. Should I have heads fly cut ? How much? Double up on gaskets?
This is my last engine build so I don't want to mess it up.
Thanks for advice
Pete

 

[JSeery]

Most builders recommend .050 over the pistons, some go as low as .040.

 

[Ol' Ron]

SBC have .035