Floating Pins how to?

So Moper... tell me, why is it very difficult to press in the pin thru the piston. I was under the impression that all that is needed to assemble the rod/piston assembly with full floaters is just a bit of elbow grease ans some spiro locks. The engine will night even come close to the 7000 rpm, more like 5500 max.

Just simply, I did all of the polishing on a set of 340 rods and would hate to give up all that work if I need new pins and pistons...