It's really hard to tell what look you're really going for with your "photoshop" job. Will the truck stay the same color(s) as in the pic or are you going with satin black or another solid color? As far as the "staggered" look, I'm not sure if there's an official rule of thumb but when you get the right combination/ratio of front/rear wheel size and tire size, it can look killer. To get a better sense of that, you're going to have to scroll thru a bunch of pics of what others used or do so some better photoshopping, including photoshopping the big wheels on the rear.

If you wanna go with the steelies look that some of the others have suggested yet still go big with the rims, you could do something like this:
1967-chevrolet-c10-front-passenger-side.jpg1967-chevrolet-c10-center-line-smoothies-with-sumitomo-rubber.jpg