Tire Width?

[Macdaddy1]

I have a 1965 C10 with the body at the painters so I can not measure or evaluate the width of the tires. I am converting over to disc brakes front and rear 5x5 pattern. I have researched and selected american torq II rims 16 x 8 with 4 inch back spacing which according to the research will fit nice. My question and concern is can I install 265 width tires and everything clear the fenders or do I need to go with a narrower tire? I am planning in the future to install 2.5 drop spindles in front and 3 inch drop springs in the back so I want to make sure these tires will still fit.