See my first post re; your problem. You might have to recheck your change in the wiring. I think that it is what is causing your problem.
For the left head lamp, the color codes are as follows:
Low beam - yellow/black
High beam - white/black
Ground - Brown
You might try reversing the white/black and the brown wires in the connector and see if that cures the problem. (I watched a Porsche mechanic puzzle over this type of problem on a new 356B for over an hour. Turns out the factory had inadvertantly switched two wires in a connector. Easy to do, results are strange, and, until you draw a diagram of the circuit, hard to troubleshoot.)
Good luck on it. Let us know what you find.