3/8in Z Nut PrintrBot Simple 1405 Holder

I switched over to a 3/8-20 threaded rod for my Z-Axis, and the delrin nut that was included is for the 3/8-18 ACME rod. It does not fit. I had a really crude solution, but then I looked on here for something better. I couldn't find anything that would work for me, so I drew up a quick sketch to try out.

Print two, put the nut inside, and then install where the delrin nut was.