trouble with trouble lights 300e

[bclem]

my 1989 300e has developed an electrical gremlin that I need some help chasing down. It has some of the earmarks of a bad OVP but with a few twists. Here's what it's doing:

At rest (not running) batt voltage (BV) = 12.71

@ idle (600rpm) BV=12.30 and Batt lite & ABS light are on bright and all other trouble lights (including low fuel) are on

@1000rpm BV=12.49 all trouble lights are on but dim, Batt light is not as bright but still brighter than other lights & ABS lite is out

@1500rpm BV=12.70 all trouble lights out except Batt is on dim

@2000rpm BV=13.05 all trouble lights out & Batt is on very dim

@3000rpm BV=13.34 all trouble lights out and Batt is still on very dim

any ideas or suggestions would be very welcome.

thanks