Trouble installing Rifle Basix Sav-1

[308and650]

Hey everyone. I tried installing a Rifle Basix SAV-1 trigger today and ran into some problems. Before I go and ask them, I thought I'd see if you guys could point out if its my fault or not.

The gun is a Stevens 200 .308

Here's a quick video I took to show my issue: http://youtu.be/W6ti6bT7xMk

Here's a pic of the two side by side: http://i.imgur.com/4EjefVx.jpg

And here's the rifle all put together: http://imgur.com/r40JOFG.jpg

To me it seems like the area where the Weight of pull spring seats is to thick. Any thoughts? Thanks in advance for the help!

*Edit: it has the detachable magazine(stays in the stock when the barreled action is removed, so that means it's center feed right? Also, the .308 is a short action right?