Way back when in the early 1970s, I bought a used 1961 Lincoln Continental off a Ford dealers lot (this was the same year Continental as the Kennedy assassination car, except mine was a 4 door sedan). I think I paid $700 for it and the dealer was selling it as junk. There were a number of things wrong with it. The power door locks did not work, neither did the wipers, and some other stuff that I have forgotten, maybe even the AC. Also there was a banging noise in the front end suspension somewhere. When I got it towed home, I set out to find the troubles. In my inspection, behind the driver's side wheel well, hidden behind the splash shield, I found a box with about 8 vacuum tubes coming out of it. I pulled the tubes one at a time and found that the ends of the tubes were split. I cut off the split ends and plugged them back in. Voila, everything worked. I then went looking for the noise in the front. it turned out to a missing bushing in a shock absorber end. A new set of shocks fixed that. I then had it inspected and got it registered. I drove it for a couple of years and then traded it in on a used 68 Lincoln.