you are probably a better mech then I but if I had re-built the carb I would know for sure where to look

do you know of anyone close to you that you might borrow a good carb to run on it ,,how does it start up,,have you fooled with the timeing or dist. at all??also check to make sure you have a clean gas filter,, I had one so clogged up one time that my truck would not hardly run at all, in fact it acted the same way,, replaced the filter and all was well,,good luck,,,,Fred