Turn signal indicator 64 Barracuda- help me understand

I got tired of tearing my turn signal switch apart every six months when my lights quite functioning correctly so I replaced my turn signal switch in my 64 Barracuda with one of the Daniel Stern replacements. When I got it back together the turn signal indicator (the single one for both R & L on the 64 Barracuda /Valiants) doesn't work. The switch is specifically correct for 64 Barracuda. I checked for voltage and there is flashing current at the tan and light green pins on the plug to the dash panel for each, one with right turn one with left turn. Bulb tests good and lights when current is passed between pin B & G in the photo. Test light does not illuminate when connected across the same terminals of the plug which indicate to me a ground is required and that is what is shown on the factory service manual diagram. My question is, how does the bulb ground when one pin leads to the bulb contact and one pin leads to the base? B and G terminals and bulb socket X. The only thing I can figure is the switch should provide ground through the turn circuit not turned on at the time and my new switch isn't doing that???
Somebody please explain it to me. Thanks!
TS Ind.jpg dash panel.jpg