Fender DRRI questions

Okay, next project...my nephew's DRRI started making crap noise and so
he sent it to me. I opened it up and noticed several things. \
The circuit board where R62 and R63 used to go was burned and
several components around there had smoke on them. After looking under
the board, I noticed several resoldered joints in that area but no
burning or lifted traces.( Cap C36 tested in circuit was 180mfd
instead of 100mfd). R62 and R63 had been clipped / removed leaving the
ends in the board. An added wire now goes from the old R62 pin (end
next to C36) to V7, Pin6 (orange wire).
There are resistors soldered from pin 4 to pin 6 on both V7 and
V8 (6V6's). The one on V8 is burnt and no connection.The one on V7
measures about 470 and is a 1 watt.
So my questions: Is there some tech update to remove these
resistors and put them on the tubes?What does the orange wire
accomplish? Are these screen resistors? How do I check bias on this
amp? If I wanted to put a bias checking plugin for my meter to test
this from outside the chassis, where would it be connected? Would I
need 1 Ohm resistors installed? Exactly where and what wattage...
Oh yes, this is a 2001 amp and all of these changes were done when
he got the amp. I suspect the Ruby tube in V7 went north. Does this
assessment add up?
I hope to go to the Austin Guitar Show Saturday after 4 p.m. See ya
there...J.P.
.

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