Which stem do I Connect a fuel line to on this carburetor?

I have an aftermarket carburetor, i'm pretty sure it's a Tecumseh Carb. It has a part number 5123F5J, could anyone lead in the right direction to finding a air box/filter for this? I would also like to know which stem I should connect the gas to. 

2017-04-11T00:37:33.809Z