In order to remove the striker safety lever and the sear spring, the sear pin has to be removed. Depending on how many times your XD has been worked on, the pin may be able to be pushed out by hand or it may require a few light taps from a small hammer. I have a set of punches (brass and steel) and a suitably sized hammer (brass and nylon) for taking care of such items. It has paid for itself many times over during the years I've worked on my firearms.
With the sear pin pushed out as shown above, the striker safety lever, the sear, the sear spring, and the ejector can be removed. Note that the ejector pin has been pushed out to the opposite side. Doing this will make it much easier to install the new sear spring. Note....be aware of the small parts that may want to get air borne (springs like to do this) as you push the pins out of the frame. One thing I've found useful is to do this inside of a garment cleaning bag. I can see right through it while working on the pins and it is more than large enough to give me plenty of elbow room too.
With the stock parts removed, it was time to reassemble using the new PRP parts. I pushed the sear pin a small amount into the frame and then slipped the PRP striker safety lever onto over the sear pin.
The next part to slip onto the sear pin was the factory sear. Again, I
gently pushed (tapped actually) the sear pin further into the frame until it was
just flush with the inner edge of the sear. I then placed the PRP sear
spring in position and tapped the sear pin further into the frame until it
engaged the other side of the sear.
More PRP Trigger Kit
4x4 Off-Road Homestead Firearms RC Flying