Just moving the battery out an inch (ie: not disconnected) helps a lot. I also did the same with the fuse panel - removed the bolts and slid it out until I ran out of slack.

I've got a PCV w/ USB cable, load equalizer, back off module, battery tender lead, & a partridge in a pear tree under the seat. Take your time, and it'll all fit.

 

What, no sink in there?

 

Get a TTS.... there's no "trying to find a place to stuff it under the seat...."

 

ya the area undermine was pretty full, i also pulled the fuse box when i installed mine and have a load equalizer in there, a pig tail connector for my stereo and the usb dam i tell ya theres alot of room under there now that i took the PCIII out.