Don't know why you would want the back wider than the front ..... go with the same all the way around .... 1.5" seems to be about right IMO

 

Just curious if you ever bought the spacers and what do you think of them?

 

I did buy the spacers. I went with an inch and half. They're holding really well. I have about 7500miles on them so far and I'm am unfortunately experiencing a bit of wobble when driving over 50mph. I've. One to the conclusion that it is ball joints and tie rods that needreplaced. Not sure if its due to the spacers or if it's just time to change them.. Ive got about 55k mileson the truck already. Other than that I'm happy with them. Its not a durastic change but it looks good.