The first one is for the Splitfire. You might have already seen it in the DIY +bow thread. Here is the link to the templates.
Click Here
The last one I just completed is for an AT2K. Instead of using the original shell to attach to the +bow, I decided to make a new shell out of polycarbonate to house the 2k's internals.
It turned out great. The only drawback is it adds a lot of weight to the front of the gun. Although I guess any integration to the +bow will add a lot of front weight. It serves as a great foregrip though. Well here are the pictures.

It's basically a box. The front and back sides of the box are the only parts attached to the +bow. They screw into the front two holes in the front where the standoff used to be. The back piece was screwed into two holes on either side near the trigger. Here is another picture.

I used a little bit of epoxy putty to secure the internals in the box. You can use hot glue as well, or anything for that matter.
Here are the templates for the box.
Link 1
Link 2
Any questions about anything please ask. Also, if you have any ideas for more integration brackets, just let me know.