You may already know all this stuff, but here's an article from Hemmings you might find interesting. 1963-1/2 Ford Galaxie 500XL Fastback | Hemmings Motor News

If you're looking to do some "upgrades" that enhance the driveabilty without destroying the possibility of going back to original, you can convert to disc brakes using Granada or 77-79 Tbird spindles. Flaming River also makes a bolt on power rack & pinion steering kit that is pretty sweet. There are also various suppliers offering factory style upholstery kits, etc.

The reason I know all this stuff is I used to own a '64 Galaxie very similar to yours except it wasn't an XL and only had the 289 engine. It was my grandmother's car and I inherited it from my dad.
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