Yeah, those old Silverados are pretty hard to kill if you stay on top of the maintenance.

And I know exactly what you mean about fixing one thing and figuring, “Well, while I’m already in here…” Next thing you know, you’ve got half the truck apart and a pile of parts sitting on the garage floor.
Hopefully it’s just that heat shield and bracket and nothing more serious lurking underneath. And definitely check that new part against the old one before you start wrenching this time. I learned that lesson the expensive way.