see if you can read the tag #'s off the front passenger side of the tranny. If the tranny is original, you'll be able to tell if it's a wide or close ratio. If it's a wide ratio, then change the rear to 3.07 or 2.88's. If it's a close ratio, then I'd probably leave it the way it is.
http://www.davidkeetoploaders.com/idchart1.htm
When you're just cruising on the street, the gears seem spaced too close, bujt when you're racing it, either drag or road racing, they're spaced pretty good, and I wouldn't change it unless you're serious about racing.