Glad you got your car back! I swapped my ignition switch yesterday, have it right in front of me and snapped a shot. After rereading your post however, not sure how much help this info will be. It's easy to remove the Volvo lock cylinder, but I'm pretty sure you have to have the key to do it.

If you reach behind dash, there is a little button at about 10 o'clock position (yellow arrow). I was able to find tiny button easily with help from a flashlight. When you insert key and turn it clockwise, while pushing the little button with a pin, the button will eventually depress and you can pull the cylinder straight out.

I don't know if other cylinders are of the same setup, and I don't know how you can depress the button if you don't have the key that goes with cylinder. Call a locksmith and ask them about it.