Larry

Your engine should have the star shapped recessed areas and round tipped pre-chambers.

You need to check the pistion projection and the distance the prechamber necks protrude past the head Piston projection should be .50 to .90 mm above the deck and the prechambers should protrude 7.6 to 8.3mm.

If the prechambers protrude too far you can reset the depth with a thicker prechamber sealing ring, if the pistons projection is too far I'm not sure what you can do.

Good luck

Tim