Hi Greg & welcome to the forums. I was in the same boat a few years ago and had already had the arm rewired by Magnepan once. Thread string here: https://forum.audiogon.com/discussions/need-a-magnepan-unitrac-i-tonearm-repaired. The 44 gauge Litz wire used in the arm tube isn't available anymore and anything else restricts the free motion of the arm on the unipivot. The guy I ended up working with tried really hard to fix it over several months, but just couldn't make it right again. I've checked over a few threads about the Magnepan arm since and this is a common problem. One respondent mentioned that there is a burr internally in the arm assembly that causes the wires to fail and can't be removed.
The final call is yours, but I'd suggest looking for a replacement arm. There have been a couple of Graham 1.5 and 2.0 units that have popped up here for reasonable money recently, and they are definitely an upgrade from the Unitrac.
Good luck & happy listening.
This seems to be a bigger problem than I thought when I bought a Unitrac. The rewire job can be done, but I'm not sure who.
I picked up this arm on Mosin's recommendation. He's the guy who makes the Saskia table. He has a couple of Unitracs rewired, but ....
There's an easy answer to this problem, but it requires drilling a small hole in the back of the armtube just in front of the pivot. Have the wire exit there instead of the bottom of the pillar. You could have one length of wire going to the preamp or use connectors on the table plinth.
My original wire is still working fine, but it would be nice to eliminate the plug in connector at the back of the headshell.