1970 Dim lights weak horn

[richardgoesfast]

Working to get this RR back on the road. Last night tested lights at night. Just about everything working which is great, but everything just kinda dim. Could this be a lighting ground wire that has lost good connection to frame? And, if so, where on the car its the lighting ground connected to frame, as I can't locate it. Got a wiring diagram but that doesn't indicate where the ground is.
Any thoughts wildly appreciated.

 

[dmartin]

How is your alternator is it charging correctly

 

[Russ69Runner]

Check and clean the light switch connection. May help. Do the head light's burn bright. Or is it the interior light's like dash and dome light. Then that might go back to the dimmer switch. Just a few thought's.

 

[richardgoesfast]

How is your alternator is it charging correctly

Seems to be charging correctly.

 

[richardgoesfast]

Check and clean the light switch connection. May help. Do the head light's burn bright. Or is it the interior light's like dash and dome light. Then that might go back to the dimmer switch. Just a few thought's.

It's like all the lights are just not quite as bright as they should be. Dash, dome, interior, parking, headlights, all just kinda should be brighter I think. They look "tired". Where is the light switch connection, do you mean behind the dash itself?

 

[Roadcuda]

Was the test done with the engine running at idle? If you rev it up do they get brighter. Also do you have the original style voltage regulator or is it electronic. The electronic will help with the brightness.

 

[richardgoesfast]

Yes, test was at idle, I walked around car in dark. I'll check the voltage regulator, not sure on that. I don't think they get brighter with revving, but I'll start it tonight and see.
BTW I love the see through hood effect on you photo.

 

[Russ69Runner]

Did not know it was all lighting. Think Roadcuda is on to something. I would check my frame ground also. But you say it starts fine. Puzzling.

 

[quikbird]

Grounds are at the headlight. Not separate special ground. Everything just grounds where it is

 

[richardgoesfast]

OK thanks for that tip QuikBird will check that out. Just tried revving motor and (fortunately) the lights are rock solid, they don't brighten or dim with the revs at all.
As far as voltage reg, here's what I got, don't know if factory or after.