03 Blaster: under construction

also, another problem that i am having is one that involves the air filter. the bolt that holds it down was overtightened at one point, and it split the arm that it goes through. i can't get it out without completely destroying the arm. so i need to buy a new one, but i have no idea what it's called. would you get it with the whole airbox? and does anyone know where i can get that other than a dealer? i'll get it from a dealer if i have to...
 
so now i've got another issue. haven't played with it in a while. when i get it to run, it's either at what sounds like a little over half throttle, or no idle at all. backfiring and popping alot too. i think that i'm gonna put in a jet kit since i'm going to have to take it all back apart. i'm open to ideas too. lol