Well, the wiper motor has a 6/64 build date. Note it is the same three terminal unit used in C-10 pickups of the 60's.
The rebuilt stuff I have used doesn't impress me in the last few years, so I have elected to rebuild the old washer motor myself. If that doesn't work, then I will punt and order a rebuilt unit.
So, I drilled out the rivets and took it apart. It is filthy with a capital F. The original grease is mud at this point... with dirt and a dead bug or two in there that I fished out. That explains the grinding noise...
The armature/windings look brand new.
The internal wiring is shot. It has cloth insulators that are fraying.
The brushes look... well brushy in my non-expert opinion... but a little worn/short. The springs holding them in tension are kinda rusty and suspect at this point. Not sure if I can replace those springs though as I don't know anything about getting new ones of the correct type/tension.
The seal between the firewall fell apart upon removal, so I will order a new one.
I am ordering the brushes and the parts to rebuild the washer assembly too. I have not gone inside it yet. It clicks when the magnetic switch is triggered on the bench but that is it. I expect all the seals are shot.
I have redone the wiring harness from the dash switch to the wiper/washer motor and used mainly new packard connectors (two original connectors remain since I could not find replacements for them). I just de-pinned the old connectors and inserted the new wiring terminals into them. That is the last of the original wiring that was hooked up to anything, so I can rest a little easier. There are still courtesy lights and feeds that are not hooked up and I will get around to replacing those wires later on before hooking them up.
Other stuff I have made "good enough to use", but not really done yet:
Battery Tray lined with polyurethane.
Battery hold down made and hooked up, I still need to weld reinforce the cut/bend points and then plastic dip it all. Will further need to weld bolts on to the sheet metal to mount the hold down with a wing nut instead of requiring tools for removal.
Battery isolator mounted with bolts/nuts. I will replace the blind nuts/spacers behind the firewall/cowl with nutzerts when I get some more time to drill out and install them.
I have not had time to get the horn mounts done, but the horns and wiring both test ok.