I had a Fender Clapton Strat, then I built another using a MIJ body and a Warmoth maple neck. Fender makes them with extra routing under the pickguard for the circuit board and in the trem cavity for the battery. I don't think you will be able to install it without routing the body.
I highly recommend the circuit. I also put Bill Lawrence pups in it, along with some different switching options. Big improvement over the Fender Noiseless.