1. idle, slide screw
2.idle/low speed air adjustment screw
3. high speed adjusment
4. choke/topplate (this is where the throttle cable goes though and attaches to the slide).
5. tickler (pushes the float down to prime the fuel)
Dunno what the factory suggestions for needle settings are, last one I ran I just sort or set it all about 1 turn out and adjusted from there.