Security Six Rear Sight Blade Help

[burn45]

I just purchased a Security Six 357 2-3/4". The rear sight blade was missing. It did have the screw and spring. I ordered one from Numrich item # 225710B. I can't get it to fit the slot. It has a dimple on the blade that will not let it go in the slot on the sight. This is the first time that I have tried to replace a blade. Am I doing something wrong or did I get the wrong blade?
Thanks for you in put :banghead:

 

[gb6491]

Older Ruger sights do not have notch in the sight body; newer ones do.
If your sight body does not have a notch, you will need to flatten the dimple on the sight blade. To install: take the screw out, compress the spring (I use a dental pick, but a paper clip through the screw hole will work), install the blade in slot, and reinstall the screw. You may have to angle the blade in a little bit at the start and, if present, line up the dimple with notch to get the other end in.
Here is a link with instructions:
http://www.warrencustomoutdoor.com/ohs-installation.html
Regards,
Greg

BTW: Welcome to the forums

 

[burn45]

Thanks for the help.