Regular panel adhesive from the paint store.
About $30.00 for a small double tube, the one that takes a special
caulking gun to dispense. I don't remember the brand, but it's slow.
I have to leave it screwed together all night before unscrewing.
Not to be controversial, but that may or may not be a structurally sound repair method. Repairs to the passenger "safety cage" must adhere to stricter guidelines than other parts of the vehicle. If I may make a suggestion to all who work on later model vehicles, I-CAR has a convenient Vehicle Maker Technical Information Page that contains links to most manufacturer's technical data websites. Most of the websites cost money, but for around $20, depending on make, you can access the entire library of repair data for that make for several days, enough to print out any information relevant to the repair.