Removing battery of X5 (2002)

Hi guys,

So I've basically gotten really far on this battery... but the one thing that is evading me is this.

I can't take the battery out. This red and black thing simply refuses to come out, but I also don't want to accidently rip/break something and cause more of a mess.

I've attached a picture... how do you take this off? I've already disconnected the actual positive charge, but this block thing won't come off... any ideas?

Thanks

Oops, probably should've attached the picture

Nevermind, I figured this one out as well. Had to remove the nut with the yellow dot in it... doh