Unknown 3 Handle faucet cartridge/stem removal help

Hello, I am new here. My tubs 3 handle faucet has started leaking hot water into the tub. I am semi familiar with some cartridges and stems, but I've never seen one like this. I can remove the handle and the stem that the handle attaches to, but can't figure out how to remove the actual gray cartridge part. It looks like it has a type of keyway for lack of a better term, so I don't think it can be turned. I am afraid to pull on it at the moment until I know a little bit better what I am dealing with. I have a few pics and can answer any questions.

Any help and information would be appreciated.
Thanks,
Jeff

Anyone have any thoughts or ideas? I'm stumped and don't want to break anything.
Thanks in advance,
Jeff

Looks like it's slipped in by seeing the notches. Haven't seen those before though. Have you tried just pulling it out?

Thanks for the reply. Yea it looks like it slides out. I had a pliers on it, but it just didn't feel right and I didn't want to break it. I'm going to get at it over the weekend, and hopefully figure something out. Thanks