1974 Scamp some assembly required

Okay, that's nowhere near your engine bay. LOL What the hell are you doing up there?
Kidding of course, obviously it will all have to be addresed.
The best way, is subjective depending on the car, the person, and the budget.. First you're going to have to remove the drip rail trim, the windshield trim, and see how far this goes. Maybe not. Depends on your wallet and your intestinal fortitude. And God knows what you're going to find there. And you know how the story goes from there. When we're dealing with these cars we have to decide one of two ways.
1. Repair and replace rusted metal. Maybe a lot. Which means the car is possibly down for a long time.
2. I'll probably get torched for even mentioning it, fix it best you can, mud it up, paint it with cheap paint, run the dog s*** out of it.
Depends on what you want out of it. A real nice show car, that might take years to build, or just a driver you can beat on.