One of the choices in operating an aging vehicle is how much preventative maintenance to do.
Parts deteriorate or corrode - how much to dissassemble/replace?
I recently had a difficulty replacing the grommet in the rear valve cover of the 3.3L V-6 in my 1994 Caravan. It was leaking oil as it had hardened. Getting at it is diffculty due to the alternator bracket and other parts, it was too hard to just pop out as designed - couldn't even pull out the tube that goes into it.
I find material quality varies widely on this vehicle, some rubber materials surprising good, some metal materials like rear heater coolant lines and fuel tank retention strap clip-nuts surprisingly rusty.
You'd think that Chrylser would use better materials in recent decades, having learned in the 70s that neoprene is not good enough for engine seals.
Way back when I ran many Datsun 510s I did much PM, especially as Nissan's materials were not the equal of Detroit or even Toyota.