how to get the back seat bottom out?

[azureblue]

I need to get to the sound system power amp, and I'm told it's under the back seat. I have looked at a bunch of youtube vids, but they are not for my model car. I can feel something at the underside of the corners, but I can't see it. Can anyone tell me how to do this?

Goal is to find out why there is no sound, and I think it could be the light pipe ----