This is the incorrect forum for this subject matter (engineering forum) but simply put, you should not try anddual fuel this engine, the 1bbl carb will shake apart with the added weight of the mixer above. If you must, only the Impco 300-A will work in dual fuel mode effectively, otherwise, I would recommend an Impco 200 with a remote air filter on a dedicated fuel setup.
The spud in systems died in the 70's.
Franz
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