warlock, its kind of hackish but might do.. try a 20w 2-ohm resistor in series to each flipper coil oughtta tame them some, if not enough try 3-ohm or 4-ohm, oughtta slow them enough to be comfortable with and large enough (20w) that they wont go soft if the resistor gets warmed up some. if you have the right coils there, they might as well stay and be correct I'd think, and the resistors can always be removed easily enough whenever.

cool, my old sentinel demolition derby originally both flippers mechanically linked (yikk!), put in a right mechanism and 950 turns was so much faster than original left, it balanced nice with a big 3-ohm inline to it. definitely cheaper easier than swapping thru a bunch. simplistic sentinel sure doesnt compare to your project but resistors sure handy.