For those of you needing to replace the starter on 4.2 Trailblazer, dont be scared, regardless of what you read. or find on YouTube... You will need: 3/8ths ratchet, 15 mil socket (deep or shallow) 6" extension. 8mil wrench, and 13mil wrench OR socket.

Jack it up, take off drivers wheel, chock other wheels, parking brake... pop hood, disconnect negative from battery, you might wanna use a memory saver, I DID NOT, and got lucky my HVAC controls still worked afterwords. You can only access the starter through the driver wheel well. One of the nuts holding the starter is a PAIN IN THE ***, you cant see it, you cant even hardly reach and feel it. It is behind the solenoid. Holding the starter, there is ONE BOLT, and ONE NUT. The NUT goes on a stud machined into the engine block. Its on the back side you cant see. If you can past the PAIN IN THE *** hidden nut, you are home free.