This is V1, I have another idea that after this I will come with V2
It is a 2 part assembly that is tight fit.
The ID of the adapter is fitted with one of mine carburetors, so far all OK.
One hack may be necessary and that was not on all the cases; to enlarge the holes on the carburetor mounting
to 1/8″ / 3.2 mm .
If your carburetor does not fit tight, use some RTV gasket in tube.
NOTE: only red part is include in to the sale the back plate and carburetor are just to display the part.