Mine looks nothing like that. It is literally a block bolted under the master cylinder on a stamped bracket.

To tell the truth it looks more like a proportioning valve than anything else, but it is the ONLY thing in any of the brake lines.

I have a factory manual for this truck on CD, and this unit is never shown or illustrated anywhere that I have found. As for the bleeding, it say to bleed the system as you would without ABS, only the four wheel is a covered for bleeding.