head lights pulse after bypassing my bulkhead

Interesting, Kit; maybe in your case, it was more at lower low RPM's like at a low idle (500-600 RPM)? The flicker rate would be visible. (The OP's issue was at high engine speeds.)

Well, very intersting info from 60jerry above; hope that is the issue for the OP! Perhaps the higher resistance in the VR feed creates a time delay in the circuit when it tries to change the field current; the field inductance would be part of time delay.