Will, this is second hand info but I believe it to be true:
To adjust power levels:
VR 1001 160 M.
VR 1002 80 M.
VR 1004 40 M.
VR 1006 30 M.
VR 1007 20 M.
VR 1008 15 M.
VR 1009 10 M.
The adjustment for FWD ALC is VR 1017.
This info came from NO4J who has used it to increase the power on his
990. I don't know just how high you can increase the power with either
the internal switching supply or an external 12 volt supply, but as you
are adjusting, keep on the lookout for a sudden jump in current, that
might indicate a thermal runaway of the finals.
Good luck, Pres
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