[Heliarc]

That's not really a good test for a coil.To test the coil you have to set your meter to read ohms and test the resistance across certain points for it.I forget how to do it, or what the values should be though.Besides that, if your coil was indeed bad, that isn't too expensive.I think you could just slap in an automotive coil without changing anything else.

Of course you can do the HEI at any time you want.It will most likely fix your problem.But it sounds too trial and error to just do that without knowing exactly what's wrong.