340 Piston to valve clearance w/RHS heads
I have exactly the same build. Same crank and Pistons, same RHS Heads.
I milled .021" down the top of the Piston to zerodeck. ( depends on your deckheight!)
Then i had the clearance of the standard felpro Headgasket of .039.
Runs very strong and very good!
I ran the Lunati 60402 in it and clearance was no problem!
Change now to the 60403. Will hope the clearance is still ok.