well i decided that im goign to try and get my girlfriend into fighting games by making her own stick. i had my old tvc fight stick just laying around. tore the guts out of it painted bought a sfiv 360 fight pad. my question is here is i still want to use the guide button on the stock tvc panel. would i solder two wires to the guide position on the tvc pcb and cut the power cord off the pcb as well and for the directional inputs im going use the stick harness from the tvc stick. can i daisy chain the grounds from the sfiv fight pad together?
Yes, you can Daisy Chain Grounds.
However, the TvC PCB must be powered for the Home button to be used. If no power, then it will try to suck the power out of your 360 fightpad through the guide. So, you must connect the VCC from the TvC stick to the VCC of Fightpad, and connect Ground to Ground, and then connect the guide point from FightPad to the Guide point of TvC.
You can do with Turbo button, too, since SFIV FightPad supports Turbo.
If he cuts the Traces of the Signal and Ground for Home, then VCC and Ground does not need connect.
what do you mean cut the traces on the pcb?