Thanks for keeping the ideas coming. The more I hear the more I am thinking that some form of adhesive mounting may be the better idea in this case. I will be able to thoroughly clean the interior surfaces where things need to be mounted on the floor. With that in mind a high strength epoxy holding down some shallow uni-strut would hold the radios, siren and lighting control unit with ease. This vehicle sees very little road time so vibration and road flex will not be a problem. Fortunately for me the exterior lights and light-bar already have mounting bosses welded to the body for me to use. Another plus for the epoxy is that I will not have to worry about what is on the other side of where I would be drilling and I won't have to worry about the pretty new paint on the outside for the side mounted equipment . I will keep you posted when I get the rig back and start this project.

Robin