Charlie, I don't know if that wire is replaceable by itself. Replacing the wire probably can be worked out, but I think the original remedy was to replace the complete armored cable assembly. And I don't know if the bracket on the coil can be removed from the coil, or if the bracket is part of the coil "can." But first thoughts on the warm stalling is that the coil itself is suspect. Coils tend to fail with heat. For the purpose of testing, see if you can rig up a different coil in place of the existing one. The coil end of the armored cable detaches from the top of the coil, so you should be able to remove the existing coil and mount a later model coil in its place, then run a jumper wire to the "new" coil and see what happens. If the stalling problem is eliminated, the coil is the suspect, but I don't know if you will ever find an original replacement. Some of the vintage parts outlets might have the proper replacement. At risk of backlash, you can use a 12V coil if it doesn't have an internal ballast resistor. 12V coils with an internal resistor will be marked as such, usually stamped in the coil case. The main difference between 6V and 12V ignition coils is the turns ratio; primary to secondary turns of wire. I think the 6V coils have a higher turns ratio, but primary resistance is close to the same for both, around 1.6 ohms. I don't have coil resistances at my finger tips, but I can probably find some if I look hard enough. Maybe others at this site can give better information on your setup. That armored cable setup on Chevrolets was not used after WWII, or maybe after 1946. Hope this helps, although maybe not much.