My Bally Beat The Clock has 4 Flashers in the playfield and 4 behind the backglass. Only 500 machines made in the run. I know of 5 or 6 other BTC's and they all have GI where the flashers on mine are. Also the bonus collect hit/sound is different on mine than the other ones as well.
Any other BTC owners have flashers?
Serial Number 429
Vid of the flashers in action -