Yep its a fmf. What size jets did you end up with. I know the weather and altitude play a role but I'm just curious. I also took my exhaust manifold off and used some rtv silicone. I'm still having trouble with the idol screw needing to be all the way in. Also when I choked it to start once today it reved up pretty high and I had to shut the choke off for it to idol down. I thought it was going to diesel and it was a ice cold start.

Should the idol screw move the slide up and down? When I had the carb off I couldn't notice any movement.

Also, do you have a normal gasket for the exhaust valve as well as that squish round gasket? I put some rev sealent on the head where the studs are and also on the pipe but I ran it right away and blew it out a bit.  I got some threebond I might try and let sit for a few days and dry up.