OK, EVERY-body seems to know this machine! I spend so much time at the Silverball Museum, that I've become their 'unofficial' technical adviser concerning issues with normal operation, and proper play flow of the EM machines.
Once you advance the thermometer on the back glass to the max, and light up the eject hole for the Special, is it supposed to remain lit for the duration of the game, or should it, and the thermometer, reset after the ball is lost?