[moo]

I would think the bearings were a different size then, I've never seen them out of spec. Were they the same part number?

The only spec the supplier (sometimes) got wrong was the high temperature grease the printers required (krytox was special order only).

Second set of bearings dropped right in. No pressing required.

Then something is not quite right. Every model airplane engine bearing I have encountered has been a "Fit" in the case and slips on whatever shaft goes through it. If that bearing already slips into the case it will get very sloppy if that part of the case warms up. The case housing will get destroyed.

Ed S