I'm kind of a modeling novice here so try not to be too brutal on me. Anyways.. have fun with this and if you make improvements or sell it, no need to cite me or anything. Just go to it. It's yours.

Printing upside down is on purpose. When printing, make sure you include the brim. And also the slotted pins (which were kind of bad to warp on the bed but that didn't really matter) will need to eventually be glued into place (they're left out so that the print can be done upside down). Also, I purposely merged the two main pieces in the slicer so be aware of that (this site wouldn't let me upload them merged due to the “error”).