How to open case on bulb failure module?

Hello all
Again trying to resolve the last few issues on the MY88 car I am working on. A few days ago I posted about a problem with an intermittent turnsignal. I had diagnosed the problem to be with the one bulb failure module and I am now trying to get the case of that module open so I can look for any cracked or otherwise suspect solder joints on the circuit board.

Can anyone provide some hints as to how to get the case open on one of these? I see there is a crimp in the case near each of the four corners. I have pried those crimps back but so far that has not resulted in any movement or looseness that would tell me I am making headway towards being able to get the case apart on this module.

Any hints would be appreciated.

Nevermind, I pried some more with a small screwdriver and I got the case apart.