RepairPal Certified shops can diagnose and repair your 2002 Chevrolet Trailblazer. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
You have to remove the Fuel Tank shield and it is under neath.
You will need some tools to release the special fittings.
here is site that has info and diagrams that will help you.
http://bit.ly/mitchell_repair_manuals_online