Hi Ron
On some of the electronic ignitions they need to be fed power to the circuit board at points plate position, so there is an extra wire on top of blue and yellow going to this.
This is usually taken from the black ignition switched feed to rear brake light switch.
Sometimes float valves can be settled by a gentle tap on side of bowl with screwdriver handle.
Aftermarket valves are notoriously unreliable, best to use originals unless damaged.
Others have found it necessary to clean brass float seat area with a clean soft wood dowel suitably shaped to fit.
If carbs have sat in freezing conditions sometimes the oveflow tubes splits so fuel leaks even when level correct.
You can test by removing the bowl and filling with fuel and I use a x10 magnifier when examining carb parts.
Also check that the float bowl drain screws O rings are fitted and area is clean.
+1 on not checking spark whilst fuel/vapour is around. Best to shut off fuel if there is a leak and you want to check spark.
Sorry if not applicable to your set up or I have duplicated any points already covered
