Very good news, I finally found a machine shop to machine my coupler! I am going over the finer detials with them and got a really good price. I hope to be able to drop off the components before I leave on vacation so they can work on it when they get the time. Tomorrow I am going to call them and see if that works for them.
I have also done a nice high voltage test with my controller using DeWalt batteries in series. I had 66 volts and it worked great. I used a weed whacker motor and took a video of it, but for some reason it is having a hard time uploading.