I did not have to make any modifications to make it fit on my Stevens.

On the back of the trigger housing, there is a raised lip. I when I first tried installing the tigger I had this raised lip inside. I had to put this raised lip right on the edge.. not inside. Then the hole lined up enough to get the screw in.


Here's a video that gives a good close up look at the trigger after it was installed. Hopefully this helps: