Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
The tool in the link is too short for SOHC carbs and why would you want to make one when they are cheap to buy >>> https://www.ebay.co.uk/itm/352431313684?hash=item520e8b1314:g:kT4AAOSwLSZb~mov
I have the longer and IMO the better version. Sometimes the carb sync screw is quite deep down inside some carbs where that one would struggle to reach or the frame would get in the way. I'll post a pic of it with dimensions if your interested Erny.