Transmission filter change

I'm changing the fluid and filter in my transmission today. The new filter came with a metal and rubber "O" ring type thing that fits up into the intake hold in the transmission. The filter then gets pushed into this "O" ring thing. I made the mistake of removing the old O ring and now I cannot get the new one in there. Any suggestions?

'99 Intrigue 3800

Lube it and use a socket or some similar device to drive it into the bore, careful here though.

The socket worked like a charm. Thanks for the advice.