I tried to replace my CV joints today but the allen head bolts don't seem to have been touched in 40 yrs. Even my impact wrench couldn't get them to budge. I'm afraid of stripping the head if I'm not careful, but they ain't movin'. Any suggestions ?
My '74 doesn't have nuts on the hex bolts. Another undocumented difference with the 74's I guess.
Post-cleaning
After the cleaning a got some penetrating oil in there. Ill let it soak overnight. I also picked up a bigger air gun (500 ft-lbs). Ill give it another shot tomorrow.
Might that be a lock tab under the bolts? Maybe not stock but what you are describing is exactly what happened to me when I missed some lock tabs on some bolts (not e9 shafts) a long while back. I beat the heck out of the things until I discovered the lock tabs. Yes, the Allen heads are round but possibly there is another clever method of locking we all have missed.
can you try an impact screwdriver fitted with an allen head ?
IMHO that would be the answer