Would stock wheels from a 2010 deluxe fit on a 2005 fatboy? I know it would need different bearings, but any other reasons it wouldn't work?

 

They should with the bearing change. Check hub width from both sets of wheels.

Stone

 

The hub width or spacing of the pulley will most likely be your biggest concern.

 

Might have to machine or get new spacers. I had the same issue with my rear wheel swap going from 2008 cross bones to 2007 night train. Same wheel size and everything but they switched the axle size. The bearings went into the wheel with no issue but spacing was different.