Here's why I HAD to swap tanks.
Note to self; PPO's JB Weld and epoxy is not an acceptable method to mount recessed fuel caps.
OK you guys convinced me (sort of) I have a shiny inside 79 special tank with dual vacuum petcocks. All the holes / fittings on the vacuum petcocks are bigger than the earlier non vacuum ones. So a pair of those should flow well (enough fuel). So this will be the "mule" tank at least. And the fittings are large enough to seal to 5/16" fuel line with worm clamps.
While looking the petcocks over I answered a question I have thought/wondered about a few times. When a vacuum petcock is in the "prime" position it is pulling from the reserve port not the "on" port.
Bonus find today a 3/8" PEX brass 90 from the local plumbing isle (2 for $3) is a great match for 5/16" ID fuel line and the big fittings found on VM34, VM36, VM38 carbs.
Helps with fuel line routing.
Also today The UNI filters were too long, hit the battery box and were "scrunched".
I cut some foam out of the sides at the rubber carb adapter end, removed the old glue from the rubber, cleaned all oil off rubber and foam with soap and water, then carb cleaner, and finally acetone. Glued foam to rubber with 3M "bondo" plastic bumper epoxy. VERY strong flexible bond. If I ever have any issues with that glue bond I'll report back.
Final note for today. Anytime you have the petcocks off remove ALL paint from the sealing area on the bottom of the tank. Razor blade paint off then sand the metal smooth. New o-ring seal = no leaks. I always find paint stuck to the O-ring so fuel can leak between the paint and the metal tank.
Too many other things today to finish the petcocks and fuel it up, but hopefully tomorrow. Then I might be able to do a "real" road test of "madness" and find out if the carbs have half way close jetting.
Advance to the head of the class; what is "wrong" with those carbs?