Greg
I've worked on a lot of E bodys and changed a lot of dash pads.

You can save yourself a LOT of cursing, a LOT of skinned knuckles if you just remove the dash assembly as a whole. Take it in the workshop and change the pad on the bench.

In order to get at the 12 nuts holding the pad on, you'll have to dismantle most of the dash anyways...

Trust me, you can remove the assembly in under 20 mins.