The seal carrier may have 2 small holes on the back side like this one – if so, insert a small punch thru those holes to knock the old seal out. Then drive the new seal in with a socket of appropriate size.
Bob
1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20
“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."