Well, just called United Engine and Machine and they told me the correct place to measure the KB107 piston is 0.550" above the skirt. He also told me the "0.030 over piston" measures in at 4.0285"! So they aren't quite 0.030 over...
All pistons are undersize. The BORE is what to measure! A 4.030 piston will always measure small for the clearance. Wouldnt work too well if the pistons were the same size as the bore.
