It's easy to convert from a generator to a single wire alternator. Search the Internet and hot-rod places. This has been common since the 60s. To make it even easier, you want to get one of those alternators with the built in regulator so that you can do what is called the "single wire" conversion. That's the good news. Now for the bad news.
Your ammeter won't work. You'll need to find a bracket. You'll need a new fan belt, and you'll have to figure out what size it is. You'll need to do research and spend money to find all this stuff and then make it all work together. All these problems are very solvable. But if you're like me, the process will involve lots of workarounds; waiting for parts in the mail; driving the other car to the parts store; and, generally solving problems 16 times.
When you're finished, what have you got? No ammeter; something that doesn't look right when you open the hood; and, more juice at idle. What do you need more than 30 or 35 amps for? Killer stereo? Aircraft landing lights for headlights? The stock generator will produce enough juice for the standard equipment for these cars. If you've modified the car so much that its electrical needs are greater, then that's another matter.
