Topic: Two-wire tail light

[tfrasca]

I've searched around and looked at wiring diagrams, but I can't quite figure this out.

I just got a Lucas-style tail light for my '76 550, and it only uses two wires. It grounds through the housing. The trouble is, that each wire coming from the new tail light seems to want 12v. One for each filament. That's fine for the tail light, which is just one filament. The problem is that our brake light switches provide a ground, so I'm at a loss for how to complete the brake light filament circuit.

Has anyone wired one up recently?

Thanks,

TF

[DH]

Brake switch connects  grn/yel wire (brake lite filament) to black wire (power). bulb socket grounds thru a green wire connected via a spade connector on bottom side of bulb socket, under the tail light bracket on honda lite. it needs the dedicated ground because the tail light housing/bracket is rubber mounted.
Black wire on switch is 12V, not ground.