[SAJ]

Wingski the glass fuel bowl should be full of fuel not half full of air as in your pic. Loosen a union nut after the bowl to let the air bleed out and the bowl should fill. Then test the fuel flow after each of the filters and see if it is a full pipe-diameter flow into a catch can rather than a piddle into a catch can.
Those filters may be restricting the flow and causing lean running.
If the glass bowl will not fill when the top union is loose, then there is a blockage between the tank and the bowl.
We recently found an earwig in the fuel tap in a car! Each time I blew the pipe clear the earwig shot back up into the tank and then re-dived head first into the tap again after a few miles. The bowl had a partial vacuum and air in it as a tell-tale of the blockage.
In your case it is likely the filters will not flow enough under gravity feed without a pump.
SAJ in NZ
STEWWOLFE types faster than me.
By the way you have a nice looking engine set up to my old eyes