Are you located near the Racemate shop? I am on the other side of the
world, but I could get a W/P cartridge to them if necessary. I have the
online catalogue but it does not give pulley size info. BTW, the RX8
cartridge looks to be the same bolt pattern as the earlier models but
the pulley do not stick out as far,( the End Hsg is thicker}, and the
material in cast Alum.  This pic came from Rupert of asianautospares,
and is typical of his engines, you can see it is 'as new'.
Cheers, Dave McCave McC

Dave,

 I'm in the same state, (California), but not the same area. I will try to get my 20B WP to them soon, If we make the e-shaft pulley bigger than we can make the WP pulley bigger and still have the same ratio. It may be inconvenient. We might see if Racemate can supply a cup to mount on the flywheel.

Bill Jepson