Granddesign Reflection 28 BH gooseneck compatible ?

I called GD today and they agree on the Reese Goose Box but said I needed to call Lippert so I called and that's what they recommend for gooseneck towing but they couldn't tell me what wings were on my chassis with out the serial number on the pin box. So the one we bought was at another dealer ship and its in route now so I have to wait until it gets here to order one. Thanks for all the information.