K. i did it and got a level 132 Mewtwo! Couldnt catch it.... but anyone else found this! After i got missing no.

You referring to the Cinnabar Island glitch? Missingno. is actually found via another method. (However, you can find his twin brother 'M via the Cinnabar Island glitch.)

Missingno.'s actually found by performing the Mew glitch, except instead of using the Slowpoke kid on Route 25, you can use one of the Channelers on the 3rd floor of the Pokemon Tower. (There's 3 of them. 2 of them will generate Missingno., and the other one will generate Magneton. I forget which is which, but you can figure it out via trial and error.)

When you run into Missingno. or 'M, you'll receive +128 of the sixth item in your bag. So if I were you I'd put something there like Master Ball, Rare Candy, Max Elixir, or Max Revive.

Depending on what you named Red, you can see Missingno doing the Cinnabar glitch. Since people often name him ASH and that is one name that triggers Missingno to appear there, it's common.

I just named him RED and got Mewtwo, sorry for the grammar and lack of clarification in the original post. I was exhausted from school, and didnt get much sleep prior.