I think you have plenty of truck to handle the weight. We handle that much and more regularly with 24' flat trailer and single wheel gas truck.

The 36' trailer will have lots of windage... in a cross wind the hitch behind the rear axle will want to steer the truck. A good hitch - WD and stabilized - will not help that much.

A tag trailer that long and high would not be my choice behind a PU.