[Gaz64]

Like all the other advice you have received, I'll reiterate the fact that jet extensions on the secondary are for fuel starvation on acceleration.
Unless your float level is too high, they have little to do with sloshing into the venturi on deceleration.
High float level and long tubes may work, but the main well would get uncovered, then a stall condition of lean return to idle may exist.

You should have bowl vent whistles fitted to both bowls, jet extensions on the secondary with a notched float, and the float levels just under the sight plug.