Not to much I'm afraid. It was on the truck when I purchased it 7 years ago. The winch is a Ramsey (9500lb??) and I believe that the mount is made by them as well. When I bought the truck I rember reading that ramsey had a hidden winch mount for the blazers. I don't know if they still do though? The mount is attached where the bumper brackets mount to the frame.
I am going to pull the whole thing down here in the near future to open the winch up and clean/lub some stuff. The freespool lever is getting really hard to slide and the winch could use a little maintenance. It needs a new cable as well. I can take some pics of the mount for you when I do take it down, if you would like.
Only thing I don't like of the winch being mounted down there is when I have been stuck in mud, I have to lay down in the mud to plug in the controler. It is up under and behind the bumper. I need to make a plug in for it somewhere else, but have been to lazy.