The width of your wheels is going to control what tire you can run on them. Every tire has a recommended rim width, so check that against what your rims are.
The other consideration is tire circumference. I doubt your looking at a tire thats taller than the originals so if it's less it will mean your going to turn them faster than the originals which will mean a little less top end speed but you'll come off the line a little faster.
Looks, are important, at least to me they are but you didn't say what kind of truck you are making it into.
If it's a totally stock truck with stock wheels then I would be looking for a tire that carries that theme.
But alas, it's your truck and you can do what ever your heart desires.
Dan
