Trunk releases were a dealer option for 64 thru 66 Mustangs although I don't know when they were first offered. The reproductions are close to the original. There was a lever along side the drivers seat with a cable to the lid. It was supposed to work with all body styles but the lever would interfere with both types of seat belt retractors and with the extra body metal on convertibles next to the seat. There is an electric aftermarket type out but I've not seen one installed.
Jim