I've just listed a 914-6 throttle linkage kit on e-bay at:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=6763&item=1874083587&rd=1
It is a new unit from Rich Johnson. I'm not using carbs so I do not need it. Save a couple bucks if you're doing a 6 conversion!