My dash board is rather badly warped (picture included) and i was wondering if there was any adhesive that would be the best to use. the top part is plastic but underneath feels kind of spongey

 

I'm not sure if glue will keep it down.. Are you able to get it to fit underneath, where its supposed to go?

 

The edge that is lifted up is supposed to be underneath, but no it won't go back

 

Well, you might be out of luck. This is a common problem on a lot of GM vehicles. On a warm day, or after the car has been sitting in the sun for a long time, making the dash softer, and easier to work with, try slipping it back under the other piece. If you can do that, you can use some double sided tape to try to keep it there. That might be the only way you can get it close to what it should be.