Car Alarms: changing out battery on AM7, little notch, am7

Question
I have no idea how to change out the battery on my Auto Mate AM8 remote.  There is a little notch up by the key ring, so I put the end of a knife in there and twisted, hoping this would pop it open to change out the battery - no such luck - all that did was crack the whole remote.  HELP!!  ...and there's nothing in the owner's manual that tells you how to change out the battery either.

Answer
DEI PRODUCT INQUIRY
AUTO RESPONDER...

Sorry, Not something I do here as
my opinion on DEI products is well
known.

I refer these folks to either my forum
at www.installsupport.com or, try
Joe at sales@tampacaralarms.com
or, my techs @ www.installsupport.com , who might be able
to offer some insight.

Both good resources.

ALARMTEK
CARALARMMAN.COM