There's really no need to remove the firing pin or change the springs. They are virtually unbreakable. (You can flush the firing pin channel with brakecleaner or similar solvents...) A heavier spring isn't needed, even with a heavier recoil spring (because of the firing pin block), and the existing spring has at least 9 lives.
To remove the firing pin,
1) remove the slide.
2) drive out the firing pin retention roll pin, (you don't have to take it ALL the way out...)
3) press up on the firing pin block plunger while controlling the end of the slide. Pushing up should release the firing pin.
Pay attention to the orientation of the firing pin when you take it out, as it must go back in the same way. The notch in the pin must interact with the firing pin block.
Reverse to reinstall.
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