How to mount the door striker plates?

i have bought Morrison striker plates and made my own pin on the lathe to fit the locking mechanism.
Now i am wondering how to utilize the springreturned wedge(no better word for it?)
It doesn't seem to be able to use it for making the car "pop" the door as initially though it should be used for, but maybe i am just thinking the wrongway here.
Does anyone have information and/or pictures of how to mount/use them "correctly"?

I see, so the rounded side of the lock goes in against the springcharged wedge and then gets pushed out upon release.
I have another locking mechanism, so i need to review the function
Thanks Brian