The coil isn't a permanent item. I would encourage you to consider it more like a service item. I changed an old decrepid coil and got 20 miles more out of each fill up!

The peg coil is positioned in a reall horror show of a position, it gets a healthy spray of road crud, probalbty being positioned there so it remains cool.

The spade terminals just underneath the plastic of the coil housing is the place which corrodes first. if your spades appear to be wobbly, then they are beinding at the corrosion and will soon be breaking.