After laying out the top of my Dayton box for sockets, I ran into two issues. I had a blank space that no normal options would fit in, and I don't have a spot for singles, and special sockets. Stuff like spark plug sockets, and O2 sockets... So I decided to take a sheet of 1/8" Delrin I had, and use some $0.99 HF rails and make something to fit. 
I started by taking some measurements of the space. I took the measurement I got, and undersized everything by roughly a 1/8" to allow room to get it in, and out.
The spot...
The supplies...
I started by taking a cheap square, and using some vice grips clamped it down where it roughly looked right. Then used a tape to get it perfect.
I then took a carpet knife, and scored the ever living hell out of the Delrin. Until I was roughly half way through the material.
After this I took the clamps off, and put the Delrin in the vice clamping it along the seem. With a sharp push, the score broke perfectly!
Ta-Da!
Next step was to cut the short side. I was having trouble scoring it, so I took the light score I had, and using a fine tooth hack saw to it. That glided through the Delrin like butter!
The final piece after hitting it with a file.
It fits!
The hard part was the rails themselves... After figuring out the length I want, I marked, and cut one of the rails. Then I laid it on top of the other half I had left lining up the end holes, and marked it. Making sure to compensate for where the mark was compared to the first mark I did... To help imagine, I basically cut a 1" out of the middle when all was said, and done...
Then I had to drill the two holes to mirror the original end holes. To do this, I stacked the rails on top of each other, but turned 180*. So the top ones hole, is overlapping the side of the bottom one without a hole. If that makes sense... Then I took the vice grips, and clamped them together. After this, it was a simple matter of drilling, and cleaning the holes.
Then I laid the rails on the Delrin, and after position them where I wanted, I drilled the holes.
Drilling...
The final step was to drill and tap the holes to bolt the rails down. Not sure if 10-32 screws will do a great job of holding in 1/8" of Delrin, but we are gonna find out!
Finished, minus a trip to the hardware store for screws! A a better picture...
