I'm thinking the elevation changes are no big deal, it's only the length of line that will cause friction, and gas in a carb setup doesn't move fast, so essentially no friction loss.

You mentioned clear plastic filters. Are these tiny? The ones that were clear that I remember are. A good fuel filter should be about 2" dia x 4" long (just swag numbers here). Can you take a pic of them?

That fuel strainer is all you need on the suction side.