This is a remix of Nick14's handle mixed with a little of miko remix adding alignment posts.  I also modified it for M5 bolts and made the c-bore floor a little thicker.  I then added some inserts to make it pop and match some of the other mods I made to the Mini.

The 2 middle inserts can bow in and bind a bit as reported by others as well.  I just deburred the corners with an knife till they fit but HackMonkey printed at 98% and worked for him but I have not tested.