I bought a set of the allen head idle jet holders for my 40IDF carbs. just spent 5 minutes getting the old one out with a slotted screw driver in that little space while using a tiny wrench to actually turn a slotted screw driver that came with a drill I bought.
Took out the idle jet put it in the allen head holder, stuck the allen wrench in and took me about 13 seconds to put the thing back in. allen wrench never fell out, very very very very easy. the pain in the ass just became very simple...