Cheers Dave.
Last stupid question (I hope)- on cylinder 3 where does the carbtune adapter go if the vacuum stub is on the intake manifold?

The vacuum hose needs to be blanked off when checking general engine running when fed from remote tank.

The vacuum hose can then go straight on to one of the balancer inputs along with the other 3, when adjusting each of the carb air flow.
Connect them in cylinder order so you know which one to watch when you are adjusting.

Depending on type, I always calibrate mine before starting.
With engine warm and ticking over evenly, connect any cylinder to each of the 4 gauges in turn to check that they all read the same.

Dial gauges can be adjusted, tube type should be accurate, if not allow for plus or minus reading .