Does different belt size matter?

[shenk10]

I have an ls2 out of a trailblazer and the power steering pump and reservoir wont fit in between the frame rails; however, the truck pump and reservoir fit fine. The pulley on the truck pump is bigger though. I was wondering if I ran the truck belt size which I assume to be a little bigger since the pulley is either a half inch or inch bigger, I can't remember. Will this affect performance or how the truck runs? I could try to take the pulley off the ls2 pump and put it on the truck pump. Any suggestions and knowledge would be great. Thanks