04 te450 fcr conversion - anyone done it?

so i'm putting a fcr 41 in place of my now junk mikuni on my 04 te450.
i ordered a jet kit from jd hoping that it will be close....

what else do i need to switch? cables? airbox? it appears the intake side will fit, but i don't think the airbox side will fit without modification... do i need to get an 05 and up airbox to make it work? should i dump the tps?

i installed fcr41, fit right in - modified cables to make it work. i put a 180 main jet in it - i get backfire (with a small blue flame..) out the semi-stock (it appears previous owner cut the end off and reassembled - maybe removed some packing - i haven't investigated) exhaust - any jetting recommendations??