If you are referring to my set up and saying it produces a 3lb trigger pull you are off by about 1.5lbs. It's more like 4.5+lbs. Definitely not 3lbs. I could see it being close to 3lbs with a reduced power striker spring but I don't like those.
Yes you are correct. The "Glock" factory minus connector, standard in most G34/35 and G17L is actually about 4.5 lbs, but install a 6 lb. trigger return spring and takes closer to 4 lbs. or less.
Get a minus connector ($13.45) that gives a truer 3.5 lb. and with the 6 lb. trigger return spring ($3.00 or less) you are looking at close to 3 lbs.
http://www.brownells.com/handgun-parts/trigger-group-parts/connector-parts/3-5-connector-for-glock--prod43823.aspx
http://www.rockyourglock.com/custom/RYG-33222BK4.htm
Where to polish to make it smoother without dry/firing it a thousand or so times? http://www.alpharubicon.com/mrpoyz/glock/
And the guys suggesting just shoot it are correct as well. The trigger really isn't bad and ALL my carry Glocks are factory stock. They only get better-smoother with use. For carry many would claim the factory 5.5 lb. trigger is safer than a light 3.5 trigger or less. It could be a liability.
Lightening the striker spring in general is a poor idea with rare exceptions-special cases. Straying away from stock typically increases the risk of failure. We want reliable over light-weight, high speed and low drag philosophy. Most aware will support a factory Glock trigger for self defense over a modified one.
I would spend money ($17) on the minus connector first (a true 3.5 lb one-if that is your goal) then add or remove the 6 lb. trigger return spring and test it. It's cheap as hell and if you are "satisfied" then spend the rest on ammo and practice.