[Henry Schmidt]

Intuition gets us things like Dilivar studs and boat tailed cases. Thousands of dollars spent over decades to produce ridiculous studs and zero horse power increase.

That said, if you are going to replace the insulator blocks you might as well buy 30mm and put a taper in them to match the carbs as suggested by Andy.

As for "Wouldn't fuel have a tendancy to fall out of suspension in the 35mm "expansion ring"?: there is so much turbulence in an intake port that the fuel will have no trouble staying in suspension.
Cheers