yimmyb, I know this is a bit late but while I know very little about marine electronics, ok I know next to nothing. But one thing I did learn recently is that my Ford 351 was recently upgraded with a Pertronix I module, just before I bought it. After doing my own research I discovered that with the Pertronix I module if the key is left in the on position it will burn up the module. Pertronix II doesn't do that.