DoomMeister's, Kuehlings Sells/Prusa X Ends

I am busy renovating/improving my sells Mendel to use linear bearings, smaller pitch belts and proper lead-screws and I noticed a few things.

1) Prusa (iteration 2) X ends don't fit the sells design, the distance between the Z axis and lead-screw is 30mm not 29mm. I only noticed this after printing a set :(. As an aside I think the belt driven Z lead-screw is a much better design than the dual motor one and will be sticking with it.
2) There are a great many x axis designs for trapezoidal (A