Dang those look close! If you put the spring on the bolt, and push the hammer and bolt together, does the sear catch the bolt?
Does the bolt fit over the power tube? I'll check tonight, but I think the bolt should slide freely over the power tube.
Also, if you remove the two set screws on the sides of the receiver, you can tap the valve out and see how it all goes together. I can understand your frustration, the bolts look identical! (FYI: Mine won't cock without air. I thought it was broken until I aired it up.