Whilst Blue Silk was a development of Green satin there was no physical commonality, the T/R, Tracker units, aerial and indicators were all different.

One LRU could have been fitted to almost any aircraft, over the life of the airframe/equipment it would be most unusual for any unit to remain in the aircraft it was originally fitted to. Line Replaceable Units were not assigned to individual aircraft serials, they often acquired a label or sticker when removed temporarily from an aircraft undergoing major servicing etc.