Originally Posted by Roelof

The upper edge of the sleeves comes in 2 thicknesses, 2mm and 3mm. The 3mm komes with most (I think all) motors with a 14.5mm crankshaft, the only different one is the REX321/421. (I can not tell about MAX)

I have fitted many different sleeves into JP Eagle crankcases and all were running fine. Yes, when using a sleeve with a 2mm upper edge you have to place more shims at the button head or use the buttonhead of an older engine. When building up an engine I always check the head clearance, it is not wise to make radical chages and trusting the right headclearance with the same shims.

But ok, I must have been lucky that all did fit......