The manual tranny fluid idea is a pretty good one, but I'm not sure about
the speakers. I just did a quick Google search, and it looks like there's
already quite a bit of stuff avaliable on speaker installation.

I think the problem is that we geezers "remember when" we just topped the
radiator up from a garden hose and that was good enough... even though
overheating was pretty standard fare for low speeds on hot days. That's just
the way cars were made in those days. Now virtually all cars are made to
provide better performance in every area with less weight and smaller size,
but for those same reasons they are less forgiving of neglect and abuse.

Mike