K341 Front seal (PTO) loose
 

I pulled on my motor to replace all the seals/ gaskets due to oil leaks. In replacing the front seal, I was able to just spin it to get it out. When i put in the replacement it also went in very easy, and slid to the bottom. I'm not used to any seal going in that easy/ or spinning like that one does. I'm not confident that the seal will actually hold. searched the web and didn't really see any references. Any easy solution to this?

Also anyone got a part number for this seal? need to replace my replacement as I buggered it up getting it out once it slid to the bottom.