Im not totally surprised that the guy you use doesnt know how to tune webers, a lot of people are afraid of them and Italian cars arent something a general mechanic would work on every day. I would suggest perhaps going to a good dedicated carburettor/injection workshop, then they will atleased know what webers are.
Im all in favour of "if you want something done right, then you have to do it yourself" or perhaps its worth contacting you local Alfa Club and they could put you in touch with a knowledgable person? If you were in Adelaide Id say swing by and I'll take care of it all for a slab of beer...
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- '77 Sud Ti - Project car - C pillar "Ti" stickers needed!!
- '88 series II 33 1.7 Weber'd - More mint than yours!