You'll have to take the carb off to be able to do this. Drill the hole in the part of the pilot jet that sticks up into the carb throat as low as possible. Right against bottom of throat, centered in the tab your seeing. The ufo came with some instructions, they mention this proceedure in there. Read thru it several times, no going back once you drill that hole. I used a dremel with an extension. Brass is pretty soft so be careful. Start with the smallest hole first.
Careful, careful
Seviersavage

I have no idea what you're up to...

But if you drilled a 55 (to what?) you're most likely to rich as a 55 is rich to begin with.

S'plain.

You know your problem has to be simple if we can just get to it.
Are you using the rubber mounting flange that came with the bike? the one the stock carb fit? It's too big for that VM by 40 to 50 one thousanths. If you didn't get the right one there is a problem.

Did you get a new throttle cable from Lancer? If you modified the stock one to work maybe it won't let the slide all the way down.

Did you confirm while the carb was off the bike that the slide had free movement all the way to the bottom? I had to modify my UFO to slide over the needle jet because it was scrubbing.

Here's an important detail, did you make absolutely sure the angle of cutaway on the intake side of slide body conformed perfectly to the ufo? no little metal edge sticking proudly over the edge of the UFO?

Are you turning the air fuel mixture screw out or left to lean it? right is rich, left is lean.

You say it won't idle, what does it do? bump up the idle speed to a medium slow idle and then lean the mixture turning left until you get an increase in idle speed. Turn slowly and listen, If idle picks up your on the right track.

When you rode it did it hesitate? buck? or backfire? midrange surge?
Those are lean running symptoms. If it is really too rich like you think pull your air filter and see, If that helps your right, too rich. If that hurts, your too lean.  

Got good gas? How about plug? coil and wire?

If everything checks out good then there is something wrong with the carb. Maybe take it off and really clean it. Sure float level is right?

This aint brain surgery, Whatever the problem you will find it if you keep looking.
Seviersavage