Bleeding the brakes can be a challenge on the old style caliper. The best way is from the bottom up. To do that you need an adapter that you can hook a hose from a pressure bleeder. I use about 60 psi. I also soldered a barb hose fitting on a spare reservoir top to attach a hose so the fluid would go into a bottle. Mine is a 61 so the reservoir is on the firewall. The adapter simply takes place of the screw on the caliper. The other trick is to remove the caliper before bleeding and hold horizontal, sometimes a tiny bit of air can get trapped on the top side of the t where it goes into the caliper. If you send me your snail mail I’ll send you my adapter and just send back when your done. Of course if you want to upgrade Webco sells a wheel and brake kit that is excellent. New style wheels with bolt on rotors vs rivet on, and the new style calipers.
Best of luck
Andrew
Afmasonry@aol.com