Found a couple of Youtube videos about balancing/synchronizing Carburetors. The first one shows using a special tool which at present I don't hve but would like to get...

https://youtu.be/MbEBya71yiI 

The second shows a bloke using plastic bottles and tubing on his snow mobile...

https://youtu.be/Y_WDF6glD5k 
Does anyone have any experience with using this type of setup?
Is it effective?

Want to get our Type 3 carbs set soon so I can get it to back on the road and then to a bloke I know who hs the correct equipment.

The tube is called a manometer. They normally need the carb to have a vac port to attach the tube too. Then you just adjust the carbs until the water levels in each of the tubes matches.

The snail type carb balancer in the other video can be bought thru Ebay and aren't all that expensive and you really wouldn't need to go elsewhere after using one of them as it's what a pro would use too.

If, however, you wish to go to the pro then using baseline settings for the carbs should be more than enough to get her driving well enough to get there.

I could describe how to do the procedure but there's plenty of web pages online detailing initial setup. Have a bit of a look on google and sure you'll find plenty. Searching for the type/make of carb you have will narrow the search. Most Solex/Webers/Dellorto's are adjusting using 2 or 3 screws so no much to them really.

Got it set to baseline and will get a snail type carb balancer in future.
The bloke I hope will do it lives 40km away and he will most likely each me how to use the snail type carb balancer.
The Type 3 has a vac port on one carb only I'm pretty sure.

Most balancers won't work on the type3 carbs because of the built in stems for the air filter attaching bolts.I used type3 carbs on the Buggy and pod filters. I made adapters to mount the filters, so my tool works ok on them.