Well this is proving to be a F'in night mare!!
The part number you gave "OMC # 172543," im told is the prestolite part, the Calco is "OMC # 172847".
The OMC 172543 / 382715 = prestolite; ESZ4009, ESZ4012, ESZ4014, ETX4001 & also = API PT112N-NP-3, I dont think these fit my connections.
The...