Am I missing something here? The low beams are the OUTER bulbs. The high beams are the INNER bulbs (closest to the grills). On my 69, when you turn on the high beams, the low beams remain on. I understand the low beams have 2 filaments. Is the OP saying that turn on the high beams shuts off the passenger side bulb completely (no high beam, abd the low beam goes out).