Re: needle clip
That's why it's not for the faint of heart....you have to take it out, use 320 paper and sand it a little at a time (chucked up in a cordless drill) then put it back and test, repeate....over and over until it's right. You can only do this if you can hear the difference. I usually take a little off until I can see it on the paper, then test.
I get the engine set so it runs well at idle and part throttle cruise, then start tapering the taper from there.