So.....where the other plate powers that were supposed to be connected to it were connected?
In short, what I am trying to understand, have you asked yourself and answered these questions? Is everything connected according to the schematic now?
Your question about what was powering the tubes, it made me look further. Remember when I said that nothing is connecting resistor #55 to the cap? .. Well, one of those three wires I mentioned (from resistor #55), it runs to the RF, but then another wire was connected from that point to the other #67 cap (call it wire #2). Basically the problem was, everything was hooked up to one single 8mfd cap. That's where the hum was coming from! I removed the wire I installed, and moved the wire #2 to the other #67 cap. All is fine.
This radio had been worked on before I got it. The Electrolytic Caps were replaced sometime back in 1945 (from the looks of it). I just replaced parts, so I don't know if I made the wiring mistake or if I just copied it. I recapped this radio back in the summer. It was one of the first radios I ever repaired, so it could have been my fault. I put it aside because it hummed. It has not been used since.
Anyways, the problem is fixed, and a huge thanks to everyone who helped me, especially Morzh!. I learned more everyday.
If you look at the sch with one #67 being at the top (or at the right most) and another being inside (closer to the 80 tube) - if all was connected to the top cap it would hum as this is the "unfiltered" voltage; the filtered one (by the field coil) goes to the one close to the 80 tube and this is where all those RF power and #55 resistors should've gone to.
Anyway, all is well that ends well.
Good job!
You know, I had gone over that schematic 100 times and I couldn't see the error. I swear, I spent hours looking at this radio. Now that I found it, I don't know how I ever missed it. Sometimes it's like unraveling spaghetti. I think I am getting better, but I don't know. Thanks a million Morzh!