pertronix coil

["Jim Boynton" <jimboynton@attbi.com>]

 I installed Pertronix Coil this weekend and it doesn't seem to like my
stock Tach or is it the Tach doesn't like the coil. Anyway I figured I match
the Ignitor installed last summer but now the Tach goes crazy at times.
  It idles fine and generally reads correctly at lower speeds. It also
appears to function correctly through the gear shifts but often at around 60
or faster it tends(Tach) to bounce around. Anyone have any ideas?

Jim