Catalytic Converter (97 Deville)

I'm trying to replace the catalytic converter myself. I have a new one but the problem I'm running into is that the end on the original converter seems to be pressed onto the pipe a little. Is there a way I can get around this?

I believe I will purchase a saw and just cut the converter off but also keeping in mind not to cut the piping that's inside the end of the converter.

I replaced the converter but in the process of replacing it, I bent the pipe that connects to the converter. Now that space is causing the vehicle to sound rough. Is there a way to fix this?

Get it to a muffler shop they can heat and reshape it.