[MrFixr55]

100mV on a 250V output tube plate is not bad.

Many sets of this vintage us rather small capacitors. However, this set has a choke before the output stage, which provides sufficient filtering that a large cap is not needed.

I agree with Morzh that the home environment is full of noise and also recommend to NOT use the electrical system as a ground Since the ground wire runs i the same jacket as the other 2 conductors in Type NM cable, the noise can be coupled to the ground by induction. A water pipe is better, but the electrical system is grounded to it. A separate ground wire into good wet sandy soil is a very good ground. There are all sorts of ways to lower the resistance of a ground by adding certain salts.

As to connections to the speaker, you can solder a Molex pin to each connection on the output transformer terminal board and crimp or solder the mate to that pin onto the cable. Use 2 pin pairs of one size for the output transformer plate and B+ connections, with a male on one terminal and a female on the other terminal of the transformer primary. For the field coil to rectifier terminal, use a different size. This will prevent confusion by making it so only one way for the connection to be made (the right one) and one pin pair of another size. Therei s a hood that covers these terminals. Make sure that the insulation is still on the inside of the hood.