What Turn Signal Flasher Do I Need

[Evo160K]

Recently I converted my softail dash which had larger indicator bulbs, like on a 1990, to a newer dash with smaller bulbs, like on a 1997.  Now the emergency flashers won't flash like before.  I was using a Wagner 552 flasher.  Would someone be able to tell me how to determine what flasher I need.  I suspect it will have something to do with the difference in the resistance of the 1990 dash bulbs versus the resistance of the 1997 bulbs.  BTW only the dash bulbs were changed, nothing else.  TIA