I just got a 1984 4 winds deck boat. I traded for work. started fine and then i gave it a tune up. everything was crudy. The boat started before i gave it a tune up . I just need to get a part # for a thunderbolt IV ignition modual . modle #mcm 898. its a gm305 motor . sn.6674576. I have been going crazy looking . And a place online that has then in stock.