Hello, In my science game that I've had for a few months, I'd saved some spacecrafts that used stacked decouplers. Now that I'm at 1.0, I can't launch with those rockets because it says: "Unavailable Experimental Parts. This vessel contains experimental parts which are not available at the moment: 2x TR-18A Stack Decoupler. 1x Communotron 16." In the structural tab, I only have a Modular Girder Segment and a TT-38K Radial Decoupler. Does anyone know how to get the stack decoupler back? Thanks!