I have a 1998 4.3 carb'd mercruiser SN 0L051****. Can't remeber exactly. The cover over the spark arrester says that it is a Thunderbolt ignition system and that "Special timing procedures are required". My srevice manual only gives procedures for the Thunderbolt "V" ignition syst. The steps say to ground the purple/wht wire and set base timing. I cant find where the purp/wht wire ends. One end is in a connector attached to the unit. I cant find the other end. Is it loose and just wrapped up in the harness or does it terminate somewhere else? Or do I disconnect the connector and ground it from there? The book is not real clear on this. And... do I have a T'bolt or a T'bolt "V" ignition syst? Thanks in advance!