Best location for Infinity on V9
http://www.norcalmods.com/graphix/v9-infinity.jpg
Best location for Infinity on V10
http://www.norcalmods.com/graphix/v10-infinity.jpg
If your going to use double sided tape to attach the chip to the motherboard, use the kind that is very thin. Not much thicker then 2 pieces of paper. You dont want the chip to come in contact with the ground plate and short out. Also use electrical tape to cover the under side of the ground plate right above the chip also, like Lufcfan said to insulate it from touching the ground plate.
If you want you can use hot glue to hold the chip down but be sure and only use two blobs on either end so you can remove it easily if need be. You must be careful if you use hot glue though because the via's on the back of the mod chip can still come in contact with components on the motherboard when you push the chip down into the glue and the glue spreads away.
Good luck!