UPDATE: the car is going to the mechanic on 2/23 for this job. It will be going to a chevy dealer whose mechanic has decades of experience which is exactly what I was looking for. This mechanic is semi-retired and picks & chooses the jobs he wants to do. When he learned I'm the original and 4th owner he took the job. I was asked to supply all the parts which I think I will need. Included with these parts will be a new EGR valve and a new Low Coolant Sensor (due to the coolant being partially drained).
I made a copy of Gnat's photo so thanks again for this. I will be seeing how the mechanic feels about just going the RTV route in lieu of pulling the rear head. Not only will the job be alot cheaper, I'd really prefer not opening that Pandora's box of potential additional issues if the head needs to be taken off.