Well, I did glue a bit of foam to the plunger head beforehand, and the chamber is reinforced by tons of hot glue. I basically had to put it together, then clamp the chamber and frame together, and hot glue all around it. I don't think it's physically possible to put it back together otherwise.
I've just finished modding my At2k with 1/2" CPVC, using 4 6 inch barrels. It works great for me, the power and range is just incredible. One thing I did was after quickly attaching the barrels with hot glue, was to grip them all at the end so they touched at the end. Then I laid down a bead of hot glue along each valley between barrels to further strengthen them, eliminating the need to tape the barrels together. I can shoot either stock darts, or stefans made from 1/2" FBR with no problems.