Newbie needs tow vehicle PSI advice

Thanks everyone for your suggestions. Yes I went way overkill with E rated tires, but it is what it is. As several have said 35 PSI is on the door sticker but that was for the original passenger tires. I was concerned about the rim PSI tolerance as well, but even at 50 PSI I would be over the weight limits of the truck (so I'd never need to go to 80), and I can't imagine any aluminum rim out there wouldn't handle 50 PSI. In any case, as I said in my original post, I'll probably start at 45-50 and see how it goes. At that PSI I'm still well under the max load of the tires. My biggest concern there would be uneven wearing of the tires. If anyone else has comments please feel free to contribute. Thanks again.