if you want to run the dynojet kit, then get the one for the 400ex. as far as jetting goes, try doing a search on here and see what people have used with stock size engines. i had one on my 300 with a 380 bore kit, and i ran a 162 main and 48 pilot, with the needle in the 3rd position. a 150 main and 45 pilot should be safe for you to start with. also, remember that the dynojet main jet sizes aren't the same as keihin jets, so a 150 dynojet is not the same as a 150 keihin.
don't buy from Paul Corbin aka TampaBoy813
01 492ex