[MrFixr55]

Hi Philco,

Is this a Christmas tree style light or a miniature 6 volt one? If memory serves, this is a 122 and you could only find a 121 schematic. If this is a 6V miniature bulb it may have been in series with the heater string but with a resistor bypassing it. If it is a Christmas tree style bulb it should have nothing to do with the filament string. If you dare and if it is a Christmas tree style bulb (or the lower wattage indicator type bulb with the same "candelabra" base as the Christmas tree bulb) remove it and see what happens.

Check all solder joints and connections to ensure that they are good mechanical connections where solder flowed well but not to the point that it "bridged" over to another connection.

Congrats on the progress and keep posting!