I just sold a 1976 Ford F-250-7200 GVWR with Helwig(adjustable) springs and 10 ply tires..Pulled a 35 ft fifth wheel with it and a 34 ft Terry plus my current 30 Ft Springdale..Fresh rebuilt 390 with new transmission with a larger radiator and tranny cooler.Worked just fine if you used the gears for the hills.
Used it with my Lance camper also..It was a good truck but it was time to update so I sold it with tears!
Yes,your F-250 will pull that trailer if you do the basics of what is now called the tow package and a WD hitch.