Unscrews from the other side and comes apart in two pieces. Classic cheap springer or nerf gun style
I thought that might be the case, which is why I mentioned the mk23 nbb, if that wouldn't fit then I'd look at any other nbb, something that doesn't need access to moving parts in the body, simplest fix would be to bed the pistol in to something like expanding foam in each half, tightly shrink wrap the pistol first to protect it, then it would be easy to trim back excess foam, reseat the gun & screw the two sides together, would be very solid.
Obviously it's a bit more involved than I've made it sound, the shell cut out for the pistol grip, ensuring the barrel is correctly aligned etc, but it's what I'd do.
While I agree, switchable fire modes etc would be neat, ultimately We're talking about a cheap & fairly fragile shell (luckily you've got two), but it's a bit like trying to make a silk purse from a pigs ear ?.
Two bodies, two projects, maybe the first a "sniper" set up, a co2 nbb with an extended barrel might fit the bill, higher FPS but simplified in use, if that works out then plan for something more elaborate with the second body ?.
Good luck with whatever you choose, keep us posted with lots of pics.
Mark ?
