Please help, not sure if Locktite 660 will keep this keyway going.
 

http://i61.tinypic.com/2qc1npg.jpg

http://i58.tinypic.com/29238fc.jpg

I'd like to eek ~30k more miles out of this before getting a 949 engine... but is that doable? Really don't want to swap it right now.

No harm in trying. Worst case is you wreck the engine....which is where you are now.

242 is low/medium strength threadlocker. You need something stronger.

At the very least I'd use the red stuff, which I believe is 271.

Sorry, I meant this fix with loctite 660 and 243:

Loctite Crank Fix - Part 1

That makes much more sense.

While I'm no expert in keyway repair, I've seen pictures of cranks that looked worse and yet were repairable.

Hustler's mom's keyway is hammered worse than that one.

Thanks. :) I went ahead with it then. Just need it to last a while longer.