The 'dually' double Lace Sensor at the bridge identifies the guitar as a JB sig body rather than a Plus (which had a conventional S/S/S Strat set-up), as does the presence of the LSR roller nut (rather than the Wilkinson nut which appeared on the first run of Plusses), not to mention JB's scribble on the ball of the headstock. in other words, it's not a Plus body with a JB sig neck partsed onto it, but a genuine sig prototype -- at least according to all visible external evidence.