BTDT
Seems to be a common problem with GM colums of the era. I have personally fixed 3 that had similar problems.
There are 4 bolts that are DEEP inside the column, I wont lie they are a PITA to get to. They are about as far as a person can go into the column with the unit still in the vehicle.
You will need a steering wheel puller, and alot of patience. The bolts in question are very odd bolts, they are TORX head bolts and they come loose. I have removed each bolt individually and lock-tite'd them and re-installed, good to go. Get your self a manual and a wheel puller and an after noon to do it. U need to go all the way into the column. The items like the turn signals, the lock cylinder all need to come out. Excercise some patience and it will be OK.