Dash Removal in 72 Demon

You'll need to go under the dash with a die grinder and cut the 5 bolts and U-nuts. Left vent box and everything else will need to be removed to get to them.
Install new U-nuts upside down and install the bolts from the bottom up to re install the dash. Just be sure your new bolts aren't long enough to push the gasket/glass. A full nut is all you need.