This is a version my Lm8uu Y Carriage adapted for the Mendelmax.
Updated y-carriage7_max with working 3 lm8uu design.
I personally use the y-carriage_al version, it has a lowered belt socket on the motor side that keeps the belt level when used with this https://sdp-si.com/eStore/PartDetail.asp?Opener=Group&PartID=60190&GroupID=346) aluminum pulley form SDP. Use y-carriage_flat if you are using a bigger pulley on Y.
I no longer believe in bed springs, nor leveling the print bed after the first time. In fact, to maxbot's credit, somehow there seems to be no bed leveling needed at all on my MendelMax. The print bed bolts together perfectly level and stays level so far (touch wood).
I printed the spacers out of ABS just in case the platform gets too warm during long printing sessions.
Print either the y-carriage_al or y-carriage_flat depending on your need, and then y-carriage_spacer.