AH, sorry, I mis-read, my fault. Yes I bypassed the external regulator. I would try testing the regulator some more. I'll re-read more carefully and see what else I missed.So this is on a internally regulated alternator it seems? As I have an external.
Also I "think" that if you unplug the regulator and ground the brown wire the dash lamp should light (with the key on). If not, check bulb and wiring and fuse, If it does, reconnect the regulator, and unplug the alternator and ground the blue, it also should light. If not, check regulator and wiring to alternator.
I'm sure someone else will correct me if I screwed it up.
Also, with everything intact and working right, if you only turn on the ignition to "Run" but not start the car, the lamp should come on since it is in the field circuit. It should come on in varying brightness if the alternator output noticeably under or over battery voltage.