phantom powering batery grip

I got the idea to add 2 6.3mm sound connectors to my battery grip since XLR is physically too large but XLR to 6.3mm is common. The battery grip needs to connect to the microphone+remote shutter port of the camera anyway for the shutter button to work. The grip would add the ability to connect microphones that need phantom power without having to sync external audio from the Zoom H4n recorder. I got me one PP2B, thinking that without the XLR-connectors and the battery the electronics should be very small and possibly insert-able into my Battery grip. Well....the electronics are small. But distributed over an overly large PCB. No way that is going to fit into the battery grip. So...back to square one. I guess I need to build my own phantom power injector.

Maybe using an inverter to get >48V from the camera supply voltabge of 7,2-10V and then an TL 783 + 2 resistors would be small enough. Then have 2 injectors from http://sound.westhost.com/project96.htm (4 zenner diodes, 4 resistors, 2 capacitors per stereo-channel.)