Ignition Module for 85 Mercruiser 4.3
 

I'm having problems with an '85 205 HP 4.3L Mercruiser and think it could be
the Ignition module. I've looked online and cannot find any listing for a
replacement part for that year range of serial numbers. Lots of dist caps,
etc but no ignition module. Was it called something else then?? It is
mounted on the exhaust manifold and is labeled "Thunderbolt IV Breakerless
Electronic Timing. High Energy Ignition V6"

Anyone had experience with this engine?