you have good compression, good spark, and fuel so you say! so hows it acting? take the f'n auto choke off, plug the inlets to the carb(Oriellys plug pack). you didnt say anything about the air filter take that off too. after that shoot starter fluid in the carb opening while starting. see if that works ifn that dont work take the pipe off and then try. if none of this works let us know and we'll go from there.
If it does work put back 1 thing at a time, and try and start it, to see where the issue is. and clean the carb again. look for fatrat440 video on youtube on cleaning the idle jet circuit and blow out all holes with air compressor. probably not airleak with the crank seals or it would have started with the starter spray well maybe post: put inline fuel filter on A MUST!! (edited)