Smart money says they're Arco anyway...
Andrew and I are setting up the deal - he's put excellent rings on 'em and I hope to use my pins as I've heard Proth's are thin.
...BTW your Bieber avatar is awesome.-Malone
The reason your piston protrusion is too small is probably because oversize pistons typically move the wristpin bore closer to the crown in anticipation of having the deck resurfaced at the same time as boring. If you don't have the deck surface milled the same distance that the pin is moved to the crown, the protrusion will change. I would pull the rotating assembly and return the block to the machine shop telling them how much to mill off the deck to have the protrusion solidly land right in the middle of the range for the 2-notch gasket. As an aside, to avoid that predicament when I am rebuilding an engine, I measure the protrusion of the old pistons first. Then I pull the assembly and measure the wrist pin to crown height of the old pistons. I then measure the wrist pin to crown height of the new pistons and do the math necessary to tell the machinist how much to trim the deck while I am having them bore the cylinders. That saves considerable time (and possibly TTY fasteners) and results in the protrusion I want.