I have an '03 Ranger XLT with Extended cab. I may have a camper shell I can get this weekend and need to know what measurements to take to see if it fits. I don't want to drive 3 hours out of my way if once I get there and it does not fit. So I want to know if I need to measure the inside of the bed, outside, or center? I haven't measured it yet because I don't know where to measure as to what dimensions are used to determine the proper cap size. Any info is appreciated, thanks.