I THINK I KILLED THE 340

The '71 340 in my car has been rebuilt but is still standard bore (with a little wear) and I assume standard deck height. I found my pistons are above deck .025-.033" but pretty consistent on each bank. I wanted to put a set of small chamber aluminum heads on but going from J-heads to aluminum would require a .065-.070" Cometic gasket, or machining the tops of the pistons or opening the heads up. The Cometic gasket is the EASY button, no doubt. My build plan has changed and I'll be going .030" over but I found a set of L-2316 +.030 pretty cheap which should end up at about the same place above deck if I understand correctly, so the Cometic is still likely going to be the solution. I may mock it up and trim the pistons back to flat deck and then have it all re-balanced, but i can do the piston machining myself to save some cost and avoid custom pistons while maintaining the compression I hope to achieve. Either way, I would have no hesitation running the thicker Cometic as long as the deck surface was correct for the design.