On my 66 Malibu, the shaft is just one continuous shaft from the flange that attaches to the rag joint all the way through the column to the threaded end where the steering wheel attaches. Naturally, you have to take the steering wheel off to remove the shaft, but then the shaft will slide out of the column from the other end. I don't know if there's clearance to pull the shaft out if the column is still in the car. I replaced my steering shaft recently because the threads were stripped. I had the column off the car to do this. Also, the shaft is supported by bearings at both ends of the column, but nothing in between.