Swapping the lock cylinders is easy and since you are swapping your steering wheel over, you are already halfway into what you need to do for the swap. All you need is a lock plate compressor tool after you get the wheel off. Use the tool to compress the lock plate spring and fiddle the clip off of the the upper column. remove the screws holding the turnsignal switch in place and the turn signal lever and then pull it gently out of the way. You will see where the lock cylinder goes in. You may see a narrow window in the casting that is covered with casting flash. Use a small screw driver and a hammer to gently remove the flashing so you can stuff a thin screwdriver or stiff feeler gauge into it to release the catch on the lock cylinder. With the key installed and the screwdriver pressing in at the hole, rotate the key and pull out and it should pop right out.
Again, you could proceed on from this point and loctite the 4 screws that come loose but thats up to you. Otherwise, reassemble in reverse.
As for the earlier question of using a auto column in a truck with a stick it can be done. One benifit of using an auto column in a stick truck is that you can mount a tach off of the nub where the auto shifter went in and not have to use a giant hose clamp.