there may be more than one reason, but if your clear filter is dry at a certain point the problem must be before it.

Well, the fuel starvation fiasco is over! I’m not certain if it was one, single item that caused my problems, or a combination of parts that weren’t working together as they should. The biggest problem I found was that the vent and fuel return tubes under the tank had different flow qualities whenever I applied pressure or vacuum. The vent line was hard to blow through and the return line was very easy to blow through, so I switched them around. The fuel return now has an ‘obstruction’ that keeps more fuel in the carbs line and the vent has full breathability.
I wonder if these lines were designed that way?
Since my problem was an emptying fuel bowl at speed, I decided to route as much fuel to the carb as possible, minimizing the return (loss of flow or pressure) to the fuel tank. I placed the fuel ‘T’ only a few millimeters away from the carb fuel port, eliminated 2 fuel filters, and replaced the restrictor jet in the ‘T’ fitting, along with the rerouting of the two abovementioned lines.
So far have several dozen miles racked up, mostly at high speed and at full 9K RPM shifts, so I guess the problem was resolved for now…
Thanks to all who chimed-in their ideas!
Rick