Lots of options on the tahoe. Assuming it is a 5.3, and using GM pump will cost around 450ish for pump. Labor is where it gets technical. Labor guide shows 3.0hrs for rear tank, or 2.2 for left tank option. But there is additional add ons for size of tank and shield or no shield, or split driveline. Depending on labor rate could be anywhere from 590 to 700 for the job, assuming no rust buckets and everything comes apart as it should. Again this is using OEM GM pump not after market which is the only pump I will use if I am going to warranty my labor.