I have a couple of early F-1 pylon engine piston / sleeve sets (K&B 6.5 and ST X40) that are so tight, that (when out of the engine, holding them in your hand) the piston will only go up to the bottom edge or mid way up the E. port before grabbing.
One ST X40 P/L I can only get the piston in half way or up to the wrist pin hole...the lower half of the skirt is hanging out the bottom of the sleeve. (that's the definition of "interference fit" aye!?)

I have measured for taper with a dial caliper, and get about half a thou...
(I'll admit that a dial caliper is perhaps not the most accurate, but it's all I have)