Okay, back in working order on the H/L now !
Had time today with wife not needing the Tahoe for work, removed the 4 ( 2 each headlight) 5MM threaded bolts and then 4 small screws along the top of the grill at the radiator support and the 5th screw at the brace in the center of the grill. This allowed enough movement to pull the grill slightly forward and was able to remove the composite headlight bucket.
Checked the connections at the back of the H/L, all seemed good, turned on lights, no light until I lightly tapped the bulb housing making sure I did not touch the bulb itself. Light came on, switched inside H/L switch on-off several times, all is good. Put everything back together, turned on the switch, no H/L.
Pulled everything back apart, took the bulb down to local O'reilly Auto, told them the problem, "you got a bad connector, not making a good connection" Sounds reasonable since the bulb looked good at the filament from what I could see. Bought a connector, went back home, spliced it in, turned on the H/Ls, NOPE ! Tap the H/L, light comes on. Back down to O'reilly Auto, "gimme a bulb for low beam '99 Tahoe 9006 PN." Got the bulb, went home, installed it, turned on the H/Ls, light is ON. Turned switch on/off about 6-8 times all good.
Found out the grill housing had been jammed in at an angle, the composite
H/L was wedged in too far in the opening. Sorry for the loonngg post but all is good now and I STILL hate all the plastic in today's vehicles.
