1969 here. Saw them for my first MLB game July 20, 1970. Tom Seaver vs. Gaylord Perry with Willie Mays being honored before the game for recently getting his 3000th hit.
Loved the Mets and liked the Yankees. Then, the Yankees were on TV every night, so I loved the Yankees and liked the Mets.
Then, I went away to college in 1980 with a lot of NY/LI/NJ people - and lots of Mets fans. I found out quick how much Mets fans hate the Yankees, so in 10 years they went from my favorite team to my most hated team.
I must be softening because I was rooting big time for them against the Dodgers, even with Donnie Baseball.
Damn, I had the date a week off. Turns out Seaver and Perry both pitched complete games. I remember Joe Foy's home run, but not Cleon Jones':
http://www.baseball-reference.com/boxes/NYN/NYN197007270.shtml