This has been discussed many times and on Fred's website in the FAQs, the only way to check functional pin protrusion is with trigger pulled and held back while lowering the hammer manually to the rest position, then measure the pin protrusion. The easiest way to increase pin travel is to reface the tip of the hammer where it rests against the frame, removing material from the frame is much harder to do, and the hammer can be replaced easily if a mistake is made, Fred states that removing material from the hammer face can cause the t-bar to jam, but I've done a couple dozen and never had a problem yet.
One caution on increasing pin travel no matter how you do it is to make sure the hammer isn't resting against the pin causing it to stick thru the standing breech slightly, hammers and frames have a lot of dimensional differences, I've had the hammer make contact with the pin directly on two different frames, so beware, this negates the safety feature of the transfer bar if the hammer drops accidentally, not too likely since it only touches lightly, but a more likely consequence is the barrel damaging the protruding pin when opening and closing the action.
Tim