I have been reading posts concerning these spark plug wiring coil kits. How to attach spring to plug wire. I shoved pointed end down center of plug wire, turned spring so wire came back outside and behind stub end. bent stub end towards spring. exposed steel 1/8th inch is pushed towards spring- seems ok- Question though I have 1 very small grommet. came in seperate small bag. 20 gauge wire dia. .. what is it ? why do i need it ?