make it new or leave it alone ?

Dude, do what makes YOU happy.

If you aren't happy with the current paint, paint it. It looks too thin on the roof to buff with all of that oxidation showing, and I can see more than a few dents that will not look good when buffed out. I'm not trying to drag you down, if it were my car I'd just keep driving it the way it is because there's still more than enough paint to keep it from rusting and I don't care what it looks like as long as it works. But that's me, and that's why all my cars are multiple colors, because I don't care as long as they aren't rusting to pieces. I'm not going to tear down a car that I can drive the crap out of just to repaint it if I can help it. But, if it's already getting parked to do a bunch of other work and you don't like the paint, well now's not a bad time. Just have a plan so 5 years from now you aren't still staring at a pile of parts and wishing you hadn't torn it down.

If the original interior is worn out, the seat covers have tears and the carpet is thread-bare then toss it, replace it and don't look back. You don't even want to think about all the things that have been on that carpet in the last 44 years, or who's butt was in those seats. :eek: I would replace the interior in a heartbeat. I know I replaced mine AND changed it to black. Yes, like every other car ever made and no I don't care. :p

The whole "it's only original once" philosophy creates a bunch of useless museum pieces. If you drive it any significant amount you can't keep it "original" without a serious grip of cash for NOS or "correct" parts because if you drive it you'll have to replace parts. It's a car, it's meant to be driven. Numbers matching, "original" cars are for boring rich guys that use their cars as bank accounts. Don't be a collector, be an enthusiast. The next generation won't think twice about banning these cars as unsafe polluting monstrosities and replacing them with self-driving computers on wheels if they've never had their heads snapped back into the seat by an old musclecar while sucking unburned hydrocarbons. Or whipped around an autoX, road, or even a drift course in an old musclecar properly updated to handle like something other than an old musclecar (ie, like something other than a barge). Because you can update these cars to best the new crap coming off the lot right now if you're not worried about it looking original or offending some other guy's tire profile sensibilities. And realistically the percentage of these cars still on the road is statistically insignificant from a pollution standpoint (gas powered lawn mowers are worse by the numbers).

But if we let these cars be museum pieces, that's exactly what all of them will become in short order, because pretty quick there won't be anybody left to remember how awesome these cars really are. Or anybody that can still shift a stick for crying out load. Put it out on the road, drive the crap out of it, and don't listen to anybody that tells you otherwise just because it might be worth more some other way.