No, it will be fine with the spacers.
This is something that some people say you need to do. It all depends on how you want the truck to look. I'm running 15x8" wheels on the front of my 46 with 3-1/2" backspacing and no spacers. There will be no clearance issues, and my truck is fairly low, and I have 2" dropped spindles in the front.
If you're wanting more of a stock track width, you'll need the spacers. Personally I like the fat tire look tucked into the fenders, and a lot of reverse on the wheels, so that's how I set mine up.
