Well, the metal sail panels are a start. They need to be modified slightly to fit around the 73+ quarter window latches, you basically have to cut a notch in the metal panel where the latch goes to account for the difference between the '70-72 latch and the 73+ latch. Then you need the earlier rear panels, as the 73+ rear panels won't fit with the metal sail panels. You will also need to figure out a way to deal with the gap, since the metal sail panels don't extend all the way back to the rear window like the 73+ plastic sail panels do. I used a piece of ABS plastic to make an extension of the sail panel to cover that gap when I converted my '74 over to the eariler '70-72 metal sail panels.
The doors are a whole different story. You either need to find an earlier set of doors, or do some surgery. One member here added the metal upper and lower panels to a later set of doors, it's shown in this thread
73 doors on my 70
