I've done this and was on at least one of the previous posts on this topic. You can basically just screw in the new jet but have to be very careful to keep the straight (after a turn or two it takes care of itself) and don't try to wrench it down too tight. Use a little oil on the threads the first time, pull it out, clean with gas, then put back in. I didn't need locktight but it wouldn't hurt.
good luck