F-14, as Steve Ritchie designed it, was supposed to have 4 flashers on the upper loop.
Williams discovered that the switch brackets would bend over time and contact the flasher bases. That would end up shorting out the switch column.
Rather than sending out an insulator kit, Williams issued a Service Bulletin instructing operators to cut out 2 of the lamps and then tie the other two together on a single circuit. This totally killed the "feel" of the game.
Most F14s came from the factory without the proper lamps or wiring, so here, we are going to restore the game to full function, as the master intended.
I get about 2 emails a month about how to do this restoration, because all the directions and videos on the web are needlessly confusing.