Need Advice, Suggestions

Yes it has an 8 3/4 now...posi 3:55 ... There is a guy in Daytona Beach that does nothing but driveline..maybe I should take the car there??? I am going to put it on jackstands tomorrow and remove the driveshaft and run it through the gears and see what happens..

Run it with the shaft in first and observe. If nothing's visable then you can pull it, just be prepared for a little fluid loss/mess depending on how it's sitting. If it looks like a shaft problem it might be worth running by there.