Short wheelbase towing

I have a technical question on towing.  Just purchased a small toyhauler, 7500. lbs gvw loaded. I want to know if I would run into problems or safety issues if I towed it with my 72 Internationl Scout.  I think that my hitch, axles, tires and brakes would hold up. Thats all been upgraded over the years. I Would need to swap in some horsepower and a tranny as the old 345 V8 cornbinder moter still runs good but would not have the power. I don't want to invest in the drive train if I'm going to be unsafe on the highway.  Any input is appreciated.