Mercury - Quicksilver 816761Q12 Spark Plug Wire Kit V8 GM MerCruiser Tow Sports Engines (5.7L) Points Ignition 816761Q12. Overview. A clean, strong spark is the difference between an engine that hesitates and one that roars to life. The Quicksilver 816761Q12 Spark Plug Wire Kit keeps your V8 5.7L GM-based MerCruiser Tow Sports engine firing reliably, whether you're pulling a skier or cruising home at sunset. Designed for conventional points ignition systems (1985-1995), this OEM set restores fac