Rod,
Buy this-
http://www.1800vw.bizhosting.com/uni_sync.html $20
1) Remove all three carb flame arrestors.
2) Find the idle adjustment screw on each (3) carb.
3) Near the idle screw, find the screw that tightens the lever on the butterfly shaft.
Warm up the engine.
4) incease idle with the idle stop screw on the center (#2) carb +/- 700 RPM
5) Put the uni_sync on top of #2 carb.
6) Adjust the uni_sync center piece (screw R or L to open/close the port) until the ball is in the middle range marker.
7) When ball is about centered on carb #2, put it on carb #1.
8) Is the ball in the same place as #1?
If not, back off the butterfly lever screw and adjust butterfly #1 so the uni_sync ball is about in the same spot as #2.
9) tighen #1 lever screw.
10) Check #3 carb with uni_sync. If all three are close in the middle range marker your done. Check all buttlerfly screws for tighness.
Reset idle at +/-500 RPM. with the #2 carb idle stop screw. Then set #1 & #3 using #2 as the base
If #3 Carb is not the same. Adjust butterfly using step 8 (above)
Final check- Go back with uni_sync and check all carbs again noting if the are all close to the same spot of the uni_sync.
Note changing one can changes others. Fine tune repeating step 8 until all three are about at the same place on the uni_sync scale.
Reset idle to +/-500.
Check periodically for correct sync of carbs. There is a small balance tube between the 3 carbs but its possible to have one carb run lean if the (3) butterflys aren't sync'ed.
Getting familiar takes more time than the actual checking the sync. Once you've done it, it'll takes less than 5 min (while having a cafe Latte).