I finally made the decision to put the iOSD mini inside my P2.
I cut through the grey 4 wire CAN-bus ribbon cable inside the P2, removed my iOSD case and made a direct soldered connection. I then reconnected the outgoing grey ribbon cable directly to the iOSD CAN-bus output to feed my datalink via the leg connector. The biggest problem was identifying the CAN-bus wires in the P2 which are not colour coded and I was helped by reading a detailed posting from Ahmed on the DJIguys.com forum.
My iOSD now resides snugly beside the Naza main controller inside the P2 and my datalink is attached to the base with Velcro allowing it to be removed when required. A big saving in weight and I am getting close on 16 mins flying with both the iOSD and datalink before I hit the 25% battery warning.