You can contact NelsonPerformance and they will send you the right pump and you'll be sure to get a genuine Walbro pump, not some knock off look alike pump. They can also answer any modification questions you may have about installation. There are a couple writeups on here about installing one. Do a little search and you should be able to find one.
See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709