A How To - Jeep Disc E-brakes on A-Body

I like everything I see except "solder." I'd investigate a cable/ chain/ wire rope (rigging) supplier and see if they can install a stronger end.

If you are good with a torch, and use care to heat sink the cable, you might be able to silver braze (used to be called "silver solder," but high temp silver, not the low temp modern silver bearing / plumbing soft solder.)