When you turn the key on, your gauge will show a discharge. It sounds like you have a shorted coil.
if your discharge seams abnormal with the key on, engine off, this would make sense. I think there should be more than 2 volts on the dist. side of the coil. If you have a stray one hanging around,
hang it and see if the engine starts. You may still have the 6 volt coil, which, after a while,
will short out with the higher voltage. Make sense? Keep us posted.
Jim Sgrig "Piewagn"