I have recently purchased a powertap elite+ with 12mm steel axle and freehub body. I would probably like to lighten it up in the future at some point (since this is WW I won't try to defend that urge) by replacing the axle and freehub body with alloy 15mm versions from the more recent models.

I believe that my elite+ uses 6901 (12x24x6) bearings while the 15mm axle models use 6802 (15x24x5) bearings. With the exception of the 1mm difference in bearing width (which I could perhaps take care of with a 1mm spacer on the drive-side to align the freehub body properly), I don't see why I couldn't just pop in 6802 bearings and use replacement axle/freehub body from a powertap SL+ or other 15mm alloy axle model.

Does anyone have any experience with doing something like this?