I'm not sure how much of the center of the stick has to be machined out to get the .750 minus .005 like Drew described.  Maybe Lancair's reason for not selling the modification is based on legal liability, letting the builder handle the machining, or maybe it's because the walls of the stick can get too thin.  Maybe it's more about sales and profits than the difficulty in doing the modification.  I'm not an engineer, so I don't want to guess.  I would pay attention to how much material has to be removed to get the bearings to fit.

 

I think a stack of washers would work as a spacer.

 

The bearings are General Bearing Corp.  #R4AZ (on the bearing), 77R4A (R4AZZ) on the package.  Lancair part #110-0008

 

They measure .750 diameter, .281 wide, .250 hole

 

The spacer is .735 diameter, .438 wide (in the center section), .358 wide (in the outer section), .500 diameter (center section), .257 hole.

 

See attached photo.

 

Mike Easley