There is always a reason someone sells a car or stops using it. So, I have probably just found out why the '65 New Yorker I have just obtained seemed a bit too good to be true. Was investigating wiring around steering column with a view to converting my reversing lamps to yellow indicators and found burnt insulation. I reckon smoke came out of the dashboard at one point.
It turns out that the thick black and red wires that run to the ammeter have shorted to each other where they ran across a metal edge on the dash structure (see yellow arrow on picture). They were bundled with 3 other smaller wires which seem undamaged. The rest of the loom to the bulkhead I have since dissected out using surgical forceps and super sharp scissors that cut right to the point, in the "Lotus position" (lying on back, head under dash) and the other smaller wires all look OK or salvageable. On the wiring diagram there is a fusible link in this circuit between the main black wire and starter relay in engine bay so assume this failed to work or was too slow to work.
Amazingly most things seem to still work on the car. Since the short was before the dashboard components I am hoping they are all still intact.
Why do they run "neat" bundles of wire across sharp edges? Disaster waiting to happen. People talk of dodgy wires in old cars, I often find the wires themselves to be OK, it is they way they are routed that creates the trouble.