outdated design !, i recommend to print the uni-X Carrier instead http://www.thingiverse.com/thing:25420
i was sick of the removing procedure every time so i made my x carriage open.
Changes are:
Just print it and mount them.
I prefer first to fix the outer linearbearing screws, then mount the carriage and tighten the inner.
Use two washers if the screws are a bit to long.
for using a V9/v10 hotend, use my Universal Wade and make a small metalplate as shown at one picture.