for whatever it's worth, i have started to use marine grade heat shrink with the glue inside for all my wiring chores over the last couple of years.
i think it's just a little more protection from whatever moisture may find it's way in and around any terminal connections.
is it really necessary ? who knows ?
but it makes me feel a little better......... i guess.............

Twenty eight years and some add ons will create issues, also i recently had to track down a dead short in the starter circuit, and the whole harness got opened up to figure it out. Turned out to be a braided steel presure line got too close to the engine compartment starter switch.

I love my ARC 8000. Been in the car for 15 years.