Thanks for all the suggestions. Results are in.
I decided to just make a new foundation board/jig. I made it out of 2 pieces of 1x12 red oak. I glued and screwed (laminated) the 2 pieces together with the natural growth rings in opposite directions to help reduce any tendency to warp. I then used the router table to make the new groves for the upper and lower bars. It's heavy, it's smooth, it's great! I then made a new electric embedding tool. I moved the switch location for ease of use. I'm using the 12VDC 7ah battery from my ice fishing, fish locator to power it. 2 taps of the switch is all that is required to fully embed the cross wire. This setup works great. NO CURVE after embedding the wires. :cheer:
Thanks to all for taking the time to help. Newbies like me appreciate it.