Either Make you own base or Modify A cheap moroso one from a swap meet like i did.. It's Ugly as all hell no one ever sees it.

I stated with a Moroso aluminum base. I am not sure on the holes / duct tape.
I probably was expimeriting with air flow or something by adding holes then taping them back off.
there is also a big hole for the Fuel inlet or choke assembly on some carbs.. that seems to be taped off too.
The Moroso base was probably too high and possibly too large of a diameter for what I needed. The aluminum is nice and soft for hammering on to reshape. I didn't have as much metal shaping skills back then (in college or just out of college) as I do now. I might attempt to make a better or nicer piece if I cared about looks. I also have a welder so I could make virtually anything out of mild steel. (limited access to proper welding equip back when I was young)

Good luck!

Greg

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