full floating wristpins vs. pressed wristpins

There is no "less right" or " possibly preventing". Your post is DEAD RIGHT. The correct way to install piston pin snap rings is flat face toward the outside, against the piston and rounded face to the pin. Otherwise, the force exerted against the snap ring from the pin can and will force the pin out of the slot, since the rounded face will allow that.

If the style of clip that gets used looks like this (see pic) there is a right way and a less right way to be installed. Look really close to how the clip is made, there is a slight contour to it's shape, put the "rounded" surface towards the pin and there for the more "sharper" edge will face outward possibly helping preventing the clip from ever coming out. Also "clock" the end gap to the 12 o'clock or 6 o'clock position, this reduces the likelihood of the clip coming out due to the reciprocating forces being a factor.View attachment 1715112503