Changing Power steering fluid

Hey guys, I have a 2003 Gmc Sonoma (4x4, 4.3) with about 165,000kms on it. I've finally decided that i should probably change it. Is it too late to worry about it, i'm having no issues (knock on wood) but figured i'd try and be nice to the truck. My question lies in which line am i going to take off where to drain the fluid. Any help?

thanks.

Remove the return line from the PS pump, (the line with the hose clamp). Plug the fitting on the pump with a piece of 3/8" rubber line with a bolt in the end. Extend the rubber line that was removed from the pump and direct it to a drain pan. Have an assistant start the vehicle and turn the steering wheel back and forth slowly while you pour new fluid in the reservoir. When the fluid exiting the line is clean, shut the engine off and reconnect the line to the pump. Top off fluid level.