Dude, hows the mounts coming along?
Been doing a few designs im my boredom, Measured the standard mount spacings, Found a decent quality bearing and designed these around them, they similar to what your planning?
Said bearing,
http://www.rbcbearings.com/spherical...on&type=Sealed
20mm internal, 35x12 external.
What you recon? Might ask my local place for a price!