Then I am on the right track. The nut on the back of the dash came only part way and then became stuck as if a thread is buggered. I'll need to find some way to keep the cable assembly on the dashboard from spinning so I can remove the nut the rest of the way. But it isn't easy.

I like the advice about the creeper! I've been using some plywood but I hadn't thought about rolling up towels for neck support because that's the killer!

Thanks!