hey man, so in the mean time of my last post, ive found out an assload of information about this thing. lol

heres a nice video for ya
BonnevillePRO.com • View topic - VIDEO: How to change fuel sending unit

The hole in the floor is going to make this a breeze. and also youll need this
GM#15824379 FUEL SENDER ~GM Vehicles-Suv's-Trailblazer - eBay (item 120684733768 end time Feb-20-11 12:59:50 PST)
The ebay one is 25+ dollars cheaper then the dealer price. watch the videos youll understand

25bucks compared to a new sending unit of 500 bucks..