In the pic of the filter cap, you can see where I re-established the ground point between the 2 cap cans. I did the same at the V1/V2 cap can ground, where the loop is also grounded. The Late 2204's have 2 ground wires coming off the PCB, the bias supply is grounded between the cap cans, and the pre-amp is grounded at the V1/V2 cap can.
After I did this, I noticed a bit less noise and eliminated some random static-ey crackles. I'm going re-visit all the grounds, and see what happens.
...and thanks for the input!
just on basis that the more the people you ask for help know, the less they have to assume. ( ex: I didnt really know you had a 2.7K ish cathode resistor, and 100k plate resistor to come up with the 290v ht figure, which was 3v within accurate... I still dont, I just took your cathode voltage, and used it to assume net current draw based on convention, that only goes so far though as the same parameters can be adjusted)