Hello. I own an old Stevens 22-410. Tennite stock. Barrel stamped A. The 22 firing pin was not operating. After removing the retaining screw I had to tap it out. I cleaned the area but I'm having a problem re inserting the firing pin & spring. It seems to be to tight to fit. I'm not sure if it needs to be pressed in or should it just fall in place. Any input is appreciated. Thank you.