1965 Valiant disc brake upgrade

I did a disc conversion on my 65 Valiant with the 70's Mopar junkyard parts and it went real smooth. I also went for a 8 1/4 rear end which allows me to run 14" wheels all the way around instead of mixing the new 14s with the rear the 13s, that would just look weird INHO.
I don't see the point of just doing the front brakes if you end up running 2 wheel sizes, 2 spare tires would be a little problematic in my view.
Also keep in mind that the original 7 1/4 rear end is a relic, holds only a few pints of lube and is weak in every sense of the word. Just replacing the wheel bearing on the old rear end will probably cost twice what a used beefy 8 1/4 rear end would cost,