I vote for custom forged!
I used Ross custom forged flattops (0 deckheight) for my rebuild (only ones that would give me my 11 to 1 static CR wich I wanted)...
make sure you have your specs ready, 'cause they will want to know a lot. Had the machinist bore the block to the Ross spec sheet, wich accompanied the pistons.(some minor clearance differences, depending on the use, like naturally aspirated or blown...you already voted for blown...so...)
one question though...
your intended heads are 10cc's larger and you still want a 10cc dish in the piston? how much will your CR drop then? I'm not into the blowing tech, but wasn't 8 to 1 an acceptable cr for blown motors, already?...
...(or was it 6 to 1...oh...well...now I can't even make any sense of my own ramblin' anymore...
)
Tom
PS.
that tractor sure put on a nice show!
hope he has the right sponsors! (like a pistonbrand)
Getting closer on this project. What a lot of work!
Stude M5 build