I used this one--
http://cgi.ebay.com/ebaymotors/BLUE-...item1e5c3eb876
(I didn't actually buy the one at ebay but if you google
battery switch you find lots of them.)
I mounted it in the toe kick area just to the right of my power
center.
I was able to open a cabinet door, remove one of those panels that's
screwed to the floor and I had access to the wires going to
my power center.
I also pulled the front cover off my power center.
I removed the black + wire from the power center and
hooked that to the switch. I added a short wire from the other
side of the switch back to the power center.
I was a 1 beer job for me cuz I had a hole saw and have done
this kind of job before.
Good luck!