The lock nut on my shift arm eccentric screw keeps working loose. The engine is all back together so try as I might, I can't get a wrench in there without it hitting in 10 places and no room to tighten! I'm at a point now where I don't see a lot of options. I can pull the shift shaft out so that the arm comes out and then I can get a wrench on the nut to tighten it. But if I do that, then I can't be sure it will still be in alignment when I put it back together. Or should have it all been loctited so that it wouldn't keep spinning? Or is the nut supposed to be just snug and the retainer tab for the nut supposed to hold it all solid? The only problem I see with this last thing is I can see tab moving left and right when I work the shifter. Several threads on the star wheel and adjustment but I can't find anything in the manual where it addresses the installation of this particular &$*@** lock nut!! Will somebody please throw me a rope!