Can you post a pic of the bridge and caps and associated wiring?
Right now the unit is in the care and custody of a technician in Florida, I'm in Idaho. I sent it to him for restoration and he has done quite a few 4000's over the years. Actually restored two of my 4000's previous to this one, he does a great job. In any event I will mention this to him and send the link.
It appears the unit was significantly modded prior to me and other than the unit will not power on, non-original transformer and pass regulator. I'm not sure the extent of issues with the unit but its in great shape and I'm hoping its worth bringing back to life. 400ish serial number.
I appreciate your help laatsch55!