Printrbot simple metal XY upgrades

I have NO IDEA why no one has made a printable XY upgrade set yet, so I decided to get the ball rolling. The following pieces (and parts list) should give you just under 12x12 inches of printable space, depending on how/where I decide to mount the bed to these. You can use a smaller/bigger bed, but the belt and rod sizes will vary.

You're going to have to play around with M211 to set the XY size. The default FW has this locked out, so here's some firmware for you.

Parts you'll need: