if the iidle screws where not installed properly they will have litte affect on idle speed. have you made sure your slides are in correct as stated eariler,cutouts toward the air filter. with clamp ons your main is way to small, try 320-350. try lowering your clip1, fourth from top. the longer needle is supose to offer more tunability, buy if yours has only 5 positions, thats not the case. usually the longer needles have 6 slots.looking back at your first post you said you have a timing plate.what is it set at, make sure somone didn't retard it on accident.
also what is your compression? low compression will make a engine impossible to jet properly. good luck