Allowable backlash

spider gears welded themselves to the cross pin due to lack of lubrication and unless the case blows itself in half the cross pin will stay in place and eat up the case-- have a scrap bin with several sure grips in that same condition
Rear end was full of grease since I have owned the car - 3 Years
Cant speak for the prior history and other owners, only god knows what they did.