I finally got it out! I ended up bending a thin screwdriver to the shape in Mike's drawing. With a lot of hammering it finally came out. I would post a picture of what it looked like when it finally came out, but I might be convicted of parts abuse.
we used a round punch from the to (opposite side from plate ) through screw holes and tapped the plate edge until it broke loose then gently scraped the gasket off not scratching the metal and afterward used a buffing wheel then a blow gun to get trash
out