Key cylinder don't turn. No lock wheel just key don't turn. I'm try some things

You'll probably have to change the case and the lock cylinder, if the key won't turn. the key has to turn to get the cylinder out.

To get the lock cylinder out you have to visualize what I am going to describe. There is a bar that runs the length of the key cylinder that pulls inward when you install the key. If you have the replacement cylinder you will see that it is at 9 o'clock in relation to the way the key is inserted (the key being 6 and 12 o'clock) Tear the front cover off of the original lock cylinder and then cut away at the front lip of the old cylinder to expose that bar. Once you can see it, insert your key, and then take a 3/32 cotter pin and spread it apart and use it to help push that bar inwards as you work to turn your key. That should release the cylinder allowing it to turn and then you can remove the old one and install your new one.