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That's not really an issue. If the car is going to be repainted, then
the work that has to be done where the vinyl is going to be similar to
where there is paint. Of course, you may have to do some extra steps,
like prime it. However, I suspect that there has to be some sort of
finish on it, even if it is missing a coat of paint or clearcoat or
something. Plus the amount of work that needs to be done will have more
to do with rust that is there now than how completely finished the roof was.

This was a 21 year old car. You're getting into antique territory with
it. If you wish to make it into an antique, it might be worth fixing up
right now, including a new vinyl top.

Jeff

 If the car had a vinyl top the steel roof underneath will be painted
so it won't rust, but I'll bet your suspicions are right and they
didn't do a full job of filling in the seams and making it 'exposed
ready' which would add more work.  The vinyl top and the padding would
hide all the imperfections.

 Plus you'll have to fill in all the holes left when you take off the
chrome edge trim surrounding the vinyl roof - unless you want it to
look like a painted roof car with funny chrome trim around the roof...

 Do it the simple way: Strip the roof, paint it, and put the vinyl
top and the surround trim back on.  Costs a bit for the vinyl, but I'm
betting it's still cheaper than all the bodywork to fill and finish
the seams and make all the trim go away permanently.

 To go better than new, have an upholstery shop make the new vinyl
top out of real convertible top fabric.  Will cost more, but will
probably live a lot longer before looking ratty or falling apart.

   --<< Bruce >>--