WHOA!
Show a picture of your measuring points. Mine, an after market Monte Carlo Bar, is
42 inches center to center of the front top of the fender mounting hole screws. To the rear of that is the factory fender screw that holds the upper A-arm bumper bracket (aka, shock shield) to the fender apron. It has the same dimension.
If you are in need of front end (and other body) measurements, get a copy of the "1966 Comet, Falcon, Fairlane and Mustang Shop Manual". There are a lot of measurements in section 17, page 5 (fig 3).
Jim