63 dart convertible? make sure it have every.single.tiny.itsty.bitsy.piece of trim and specific convertible pieces on it that it's supposed to and none of it is missing and you're happy with the shape that it's in.
check for rust, especially at the front spring hangars, top well and back thru the trunk. make sure the doors align and close right-- the strikers aren't are blowed out of the body and the hinges all wasted.
if it's a slant, you're probably okay. but if it's a V8 look for obvious signs of hackery and bobo work.
a lot of stuff for the early cars (pre 67) is specific to body and year, NLA and can be difficult to track down. a lot of stuff isn't repopped or made for the early cars as well-- ex: if the dash is wasted you're gonna be seeking out a used one or going with a custom panel and aftermarket gauges.