The last two owners of my '88 740 GLE didn't take very good care of it, so the vinyl is hard, and in some places cracked (mostly driver's seat; driver's seat is pretty bad, period). Can the vinyl be "saved" with any certain products? (already tried one application of Amor-All, didn't seem to have any effect). Dash is cracked, too, but I'm thinking that may be a lost cause.

 

That "vinyl" should be leather, unless aftermarket replacement. As far as saving it, depends on how bad it is damaged/worn, but usually, no... Getting a seat from a wrecking yard is cheap though the driver's usually are bad after 20 years... I adopt the cushions/covers from the passenger seats to the drivers-not hard.

 

The drivers seat has torn enough that I can see a cloth backing - a sure sign of vinyl from my experience with other cars... but maybe I should try a leather product just for giggles.

 

Should be leather. I don't know of any vinyl in those cars. As for abused leather, not much you can do other than stop the process. A good leather conditioner like Lexol can stop the process but it's probably a loss.

You may be able to get a leather shop to replace the leather. Especially if you remove the seat cousion and take it to them.