Underseat sub wiring

Hi all, so i have just bought an underseat sub (kenwood sw11) and before i brace the weather tomorrow and fit it, i thought i would ask a couple of possible simple but time saving questions..

First is the power wire routing, any of you who have fitted one have any tips or locations for getting the wire from the battery to the sub? unused grommits or easy to get to holes through to the cabin? I take it i can wire the earth to one of the seat bolts? And finally, did you mount behind driver or passenger? any difference in sound etc?

Thanks!

IIRC I ran the power through a grommet behind the glovebox.

Mine is behind the passenger seat simply because the CD auto changer is behind the drivers seat.