Being all original is good. Hopefully no oil leaks anyplace from gaskets drying up for so long. 66,000 miles is low for one of those engines so it should be good for a while without going into it. One thing I have seen however is that the factory used "O" rings to seal things up inside the retainers/oil shields. They have a nasty habit of getting hard, brittle and breaking up with age. This results in oil consumption as no other type of valve seal was used back then......