I don't have a clue about your method here although in theory it should work. Fluid dynamics was not my strong suit..
I do know that the drip mehtod is not that hard to do once you have been able to perform it on a system...
That being said, I messed with my first one for a good 2 hours before I could get any fuel to come out the pipe I had made (picked up a line at a wrecking yard and hack sawed it off).
Now it seems too easy when I check it on a car...
Seems that if you start with the balancer at about 30 degrees BTC you can get fuel out of number 1 which is at least a little reassuring that fuel is flowing. Then you can advance the motor to the spec and check the pump again.
The spring that Stevo is referng to is the one that fits under the pressure fitting on the IP. You did remove the spring and valve under there correct? When I did this with a full tank in the 123 the tank wanted to empty itself through this fitting...
Also you should wire open the throttle to full and disconnect the shutoff vacuum line from the back of the IP.