Ron, is this just to try them or??? I have a set in my spare carbs, not for sale though (unless you wanted the whole carb setup, IDA's w/Berg linkage/Scat traks - I just don't wanna split) if you wanted them to give them a go?
Just with you saying you may want to go back to 37's. Mine are actually 41, really nicely made too.
OR, I have a set of 37 vents spare too (possibly to machine) although I have heard real horror storeis concerning machining down the weber vents with problems with cavities in the casting especially, plus my 37's are spanish so probably have a cross-section like an aero bar
hahaha.
let me know if I can help.
Jamie