Thanks to all of you guys, I pulled the rear cover today and drained my rear diff today. I pulled the spare tire out of the way, it needed a clean up and check anyway.
My diff cover was horrible rusty with 147K. I wire brushed it with a drill attachment after hosing it down with wd40. Cleaned it up with engine cleaner and hot soap water and then brakekleen to dry. I found a permatex rust inhibitor product I had never used in the garage, so I brushed it on and it is setting up in my garage overnight. It claims to provide a good primed surface for painting, guess I will see. I have some black gloss spray on undercarriage type coating to go on it tomorrow.
I bought two small containers of the friction modifier from ford to mix into 3 quarts of valvaline full syn 75-140 gear lube. I do not have a gasket, going to have to find some black rtv type sealer.
The best part today was using the air drive rachet to remove the bolts, feels like cheating. Thanks again for the great info, wish me luck for no leaks,lol.