I am going to change my 67 GTX from manual to power steering. I have bought a complete power steering column but would like to swap only the steering shaft and coupler and not the entire column. I have only taken apart one steering column ever and it was years ago so I don't remember exactly how it came apart. So my question is, in order to pull the manual shaft out and install the power shaft, do I have to take the entire column out of the car or can I do the swap with the column in the car?