I am quite sure that I know what is wrong with your steering column. The entire tilt head attaches to the steering column jacket (the part that goes down under the dash) by means of a metal part called the Lock Plate. Please download this picture.
http://jimshea.corvettefaq.com/wp-content/uploads/2006/01/TiltColumnLineDrwg3.doc
The Support attaches to the Lock Plate with four screws. The Lock Plate has four tangs (you can just make them out in the picture.) The tangs are supposed to engage window opening cutouts in the Jacket Assembly. The lock plate and support (with the four screws loose) should be inserted into the open end of the jacket assembly and rotated so that the tangs can cam lock into the cutouts. I am quite sure that the Lock Plate was not completely rotated into the cutouts.
To solve the problem the column should be pulled from the car and the entire column head will have to be disassembled. Since you purchased the steering column as being refurbished, the supplier should make it right.
I have very complete directions on disassembly and repair of the Camaro tilt column. So I am quite sure that you could do it yourself. But it is really the supplier that did a poor job of reassembly.
If you want the directions, they can be found at
www.corvettefaq.com in the A and F-Car Steering Section. You will need Paper #1, #2, and #3 as well as Pics #1, #2, and #3. (The address for Pic #3 is above.) Additional help can always be found right here if you want to tackle it yourself.
JIML82