Fabbing adjustable pedestal light

My intended use would be for sidelighting.Putting an adjustable(height and pitch) lamp in the center of 4 plant blocks(I grow in pots currently)
I am thinking 150w cfl grow light in mogul base mounted to a pedestal using a base with maybe a pipe in a pipe.Use like a screw or bolt to secure the heigth adjustment with like a series of drilled holes. The pivoting neck and securing the socket to the neck is were I am stalled.I could eliminate the pivoting neck on some of them, but it would be alot more efficient on the outside row.Your input would really be appreciated Late.Thanks

Neo, can you draw a pic.. please : )

Yep, gimme a little bit, have a busy weekend.The girls are nearing finish, and the babies need to be set up in veg.