Wowe' B'ski that is great looking SMB rock. I wish Bill and I were there to help you make a few beds. Near the 3 ft mark (or as deep as you can with out a swim) level out a spot about the size of a car tire. Then put some marble to fist size rocks in the bottom. Then arrange around the edge of the area about 3 of those big rocks in a semi-circle with the open side toward deep water. Find a piece of log and lay it near (w/in 4 ft) of the bed and put a few rocks on it to hold it down (or tie it down). Try this - Since you will need this info before Bill and I finish our article take a look at this.

http://www.helpourfisheries.com/how_to_build_a_nest.htm