X Belt tensioner for Malyan M150

I looked at some solutions for wanhao and similar i3 clones like http://www.thingiverse.com/thing:1672640 and the remixes but they all don't really fit Malyan M150 properly as M150 comes with 3 linear bearing blocks that are different in size from Wanhao (and especially different from those upgrades ppl put on Wanhao) hence all the files I tried didn't really work. I tried editing them but it's tedious work to edit STL (why don't ppl upload source files still is beyond me) so I reworked it from