I have a Macintosh SE with a SCSI2SD drive in it and didn't want to spend $20 for a bracket. Unfortunately, the models I've found are slightly too big for my Monoprice Delta, including some of my own created prototypes for something like this.

To combat this inconvenience, I broke the project into two pieces. A single angle bracket which has 1/8" screw holes on the top and a 2 1/4" rail on the side, so it will work with more than just the bracket I'm using. To print the complementary side, just mirror the model in your slicer or CAD software of choice.

I printed two of these on my Delta and the build time was about 35 minutes.