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Ive got a rochester B single barrel that came with my '58 235, its a manual choke. I have gas leaking from the throttle butterfly shaft. I searched, and found some great threads saying the float or needle / seat. I adjusted the float so it sits way below were it should be, and it still leaks. I checked the needle and seat and don't see any clogs or anything damaged.

I just rebuilt this carb, and besides the sporadic leak, it runs great. Anything else I should attempt? My budget is so overblown I'd like to avoid buying a new carb if possible.

Rochesters were notorious for having internal leaks and throttle shaft holes wore to where they were egg shaped. If the smell of gasoline doesn't bother you too much and it runs good, drive it until your budget balances and then worry about it.

If you have quite a lot of gas coming out there then it is probably flooding. Smaller amounts are caused by a worn shaft hole. The worn hole will make the shaft loose and give a rough idle from time to time. There are shops that can install bushings in it to fix the problem.

Would the rough idle be accompanied by a audible vacuum leak? The shaft hole didn't seem bad, but yesterday I was driving the truck up and down the driveway and after a while the idle went rough, and I could hear a sucking noise. I didn't get a chance to look into it, but it would make sense that was the problem.

If you can hear it, there is a good chance that the vacuum line for your wipers came off. Throttle shaft leaks can't be heard.

I don't think you could here the leak from a bad shaft. You must have another leak somewhere. I once put the intake on and didn't get the alignment rings seated properly. It wouldn't idle and it pinged when revved.