Getting the back end of a Phantom to hang together with the battering it got from the reheated exhaust of a J79 or Spey was pretty challenging. Getting 2/3 of the fuselage of the P1154 to stay in one piece getting similar punishment from the PCB on the front nozzles would have been even more difficult. The equipment inside would have had a pretty hard time as well. I would not like to have to sign up to a reliability guarantee for the project.