Get the right manifold for the motor side to reduce the chance of an airleak. Then for the airbox side, you mod the tube to fit the carb.
What I did isn't as pretty as some but it seals real well. Go down to the hardware/plumbing store and get a rubber pipe coupler that fits the carb inlet (take the carb with you). The kind they use on drain pipe works well and has two clamps and a metal sheath attatched to it. Then get a piece of tubing cut (about 6in long)that fits the coupler. Thin-wall tubing is better, I think I used electrical EMT. Put it all on the bike and decide where you want to cut the airbox tube. On mine I cut it right where it really starts to bell out. The important thing is you want to cut it where the inside diameter of it fits your tubing, cut a little off at a time if you are unsure. Add a clamp to keep out dirt. I wish I had a pic of mine for ya but I don't. There are other threads showing similar setups, if you want to search.
