[Captainfab]

That is correct. The 2wd '60-'62 frames are wider at the rear than the '63-'72 frames. The 4wd '60-'62 frames are the same as the '63-'72's

I know that Boyds Welding makes tanks for the '60-'62 trucks, but those may be out of your budget? His for sale thread can be found in the 'Vendors Marketplace' here on the forum.The next one I would look at is the universal gas tank by Tanks Inc.