Check that you have the +83V switching on the phase outputs of the E75 card. This will ensure the FETs and TR4, TR5 on that card have not blown.
Output is on pins 2, 7, 11, 16, 20, 26.
Do you have any sign of life on any of the plasmas?
I'm interested as I am currently building up a plasma system, which has lots of issues with it.
Anthony.