Sherline Mill & Lathe DRO Display A - B Box

I have posted about using a single DRO display box for both of my hand turned lathe & mill.

I got the bug to create an A - B box to do the switching instead of plugging and unplugging the 4 wire telephone jacks.

This is an expensive little switching box however it is worth it to me.

I modified an off the shelf Radio Shack aluminum box so that the phone jacks could come in from the bottom and be protected from the machining mess. There are two types of phone jack so this is actually a little bit of a problem; the narrow ones (4 pin) for the handset are used by Shereline.

After the prove out I fabricated an aluminum cover for the underside.

The 4, 12 pin switches are the cost hit for this design.
Maybe there is someone with a better understanding of whats out there or better yet could create an electronic switching circuit and do what this does?