1914 erfurt rear sight spring help please
 

i just got an artillery 1914 refurt. bought a spring which i believe it needs i have taken rear sight apart but cant figure out how spring is suppose to fit it the rear sight it has the adjustable type rear it just fall out(the spring) any help would be appreciated did i buy the wrong flat spring i got it from sarco. cant find anything on internet

the spring has a flat end with a slight curve and the other has a nipple end i think i need to bend the end that is flat with a slght bend MORE. bend it so that so that when i put the hinge pin it wont fall out when i raise the ladder what do guys think???