I just recently finished my 200/straight 6 engine rebuild/Aussie head conversion. I went with a 2 bbl Weber 38 DGAS carb from Clifford, although it is available from other venders. If this is the route you choose to go with, I can give you prices, part numbers and venders that carry the needed parts and kits for throttle and trans kick-down cables. I also went with Cliffords dual headers and port divider. Now I just sold my last (extra) port divider last week. You don't have to buy Clifford's dual headers, but I recommend their port divider, even if you decide not to go with dual headers.
I have kept all of my receipts, so if you need any information, I can hook you up.
Let me know if you need anything.
Ted