67 chevelle former drag car now set up for the road. well all signals, 4-way flashers and
dimming the interior dome light work fine
when headlight switch is off. But when the
headlight switch is pulled things get funny
or should i say infuriating. to start if the dash lights are turned up the fuel guage will
gradualy go to empty and all signal lights & hi-beam in dash will be lit regardless if a signal is pulled left or right. but as i dim the interior dash lights everything seems to get back to normal till i'm riding in the dark and
don't know how fast i'm going. i thought it was the reostat in the headlight pull because the problem only reared it's ugly head when the
interior dash lights were "turned-up", but i have
since tried 2 new head light switches to
no avail

i've read previous posts
here and grounding seems to be a big issue,
so i tried adding an extra ground to the headlight switch (housing) but that didn't seem to work either so i'm asking for any suggestions.
the car works perfect in the daylight hours
but turn those headlights on & dash lights up
and it gets wierd
+ I like to see how fast i'm going when i'm driving home in the dark
thanks in advance