Door striker pin replacement?

My girlfriend has a 3-4 year old Zanussi oven which she bent the door striker pin on, upon myself trying to straighten the pin back it had snapped. When I was removing the pin from oven I heard something from behind the pin drop into the inside of the oven.
I have a new replacement pin now but I am totally flummoxed as to how to fit this new pin as it does not simple just screw back onto the oven frame. Any help or advice on how to got this pin would be gratefully received?