98 S10 Location of ABS Control Modules and Sensors

I am parting out a 98 S10 and this guy wants the whole abs system. I am not familiar with these parts. I think I have identified the control module, but he also wants the sensors. Where are all of the sensors located? and how do you remove them?

There's also a metal box mounted to the rear frame on the driver's side about 1-2 feet behind the fuel tank. What is that piece?

Any help from you experienced guys would be appreciated.

Thanks in advance,

Shawn