Part of the problem was, cars from that era weren't really made that well. Rust, especially...painting, before full-immersion electro-plating, rust was inevitable. Plus, the panacea of that age was, recycled steel. MUCH more prone to corrosion; and Ford went full-on into that insanity.I drove a 1966 Mustang 289 auto in college in 1982. I did lots of mods and it was a.maintenance nightmare, especially the.power steering and body panel rust. I don't like to step on anybody's dream, but old cars turn into big headaches. You will have much more fun on a motorcycle.
Engine life for Fords of that era was, about 100k miles. Which was better than the Y-block era, where life was about 60-80k. Hard to tell, since Fords rusted so fast you could hear it happening, quiet nights. That was a problem from the immediate postwar cars right up to the early 1980s.
If you got a Chevrolet small-block or big six in a truck - not a van, and you paid attention to the rust points - you could make it last.
All the little things, also would break - ANY model - but the thing was, they were easy to fix. My Pinto ate starters; and I had to replace the clutch cable twice. A nuisance, all of it; but nothing I couldn't do with a small tool kit and a small amount in the piggybank. The transmission leaked oil, but, again, anyone not afraid to use ramps and crawl under, could access the fill hole and keep it topped.
Today, the old-car bet, to save money, would be an older Corolla or Camry. Road roaches. You can't kill them. Find one without corrosion (which was not a big problem in most of them) and you're golden. Manual or automatic (yes, a few Camrys got manuals) didn't matter. That car might look like hell and have a lot of little things wrong with it, but it would never leave you stranded, and what did break, could be fixed at reasonable cost/effort.