pioneer external hd radio tuner

I have a DEH-P4000UB head unit which came with a pioneer hd radio tuner GEX-P10HD.

    This is my first pioneer head unit and first experiance with an external hd tuner.

     My question is, is there anything i should know as far as installing the unit?

Where is the best place to tie into power? Anything special needed for ground?

It didnt work too well when i had it hooked  up so i just took it out but id like to give it another shot. any help is appreciated.

let me be more specific. there is an antenna in, power supply and ip bus in and ip bus out.

do i use an antenna splitter from my antenna cable to feed both the head unit and hd unit?

Does the power have to be independant of the head unit wire harness or can i tie into that. Same thing with ground

Define "didn't work too well" Bad Reception? Poor Sound Quality? I am not too familiar with these units but I would guess you just plug your antenna wire into the HD tuner and use it for all your radio listening needs. I would guess the HD tuner brings in both standard and HD stations. You can ground the unit near where you mount it or run it with the power wires to the head unit and tie in there.