1992 LeSabre Front Speaker Removal? Help!

I am in need of some help. I recently bought a 92 Lesabre, I have bought a new stereo system for it, and I have been unable to remove the very top part of the dash to get to the front speakers. It doesnt have any screws I can see and doesnt seem to be snapped on like the front parts of the dash were. I have even now taken it to two car audio people and they were unable to remove it as well.

does anyone know how to do this without damage to the plastic?

The dash panel has about 6 screws across the lenght (at a level just under the instrumentation panel). It also has 2 screws located in the defroster air vents. You need to remove the top grate by prying up on it. It is all one piece when it comes out.

Yes, I can help. The top black piece of plastic actually does have screws (two). But they are carefully concealed and it took me a while to figure it out myself. You do NOT need to concern your self with the front of the dash at ALL to get the dash speakers out. You only need to get the top piece of plastic off. Here's what you do.

1) Get a screwdriver or similar flat object.
2) Look at left most and right most "grill" lines in the black plastic part extending across the top of the dash. If you look closely you will notice there is a square piece of plastic that can be pryed up at each end of the dash revealing the screws (7mm or standard GM size Torx). Pry them both up and remove the screws and pull straight backward. VOILA! Victory!
3) To get the old speakers out, use a 1/8 rachet with a small socket. (again 7mm I believe)
4) To reinstall the black thing slide it back into place the way you slid it out. Be carefull to engage the alignment prongs designed to go in and help hold in place (look underneath the black thing when you have it off and you'll see what I mean.