How to remove Trigger hinge

I’m making the assumption you’re talking about the LB/RB assembly based on the description, since it matches the part description the best. Super Glue doesn’t work - been there, done that. Don’t waste your time.

The LB/RB assembly has been a single part since the 1697/1698 (Elite Gen1) controllers, which is completely different from the 1537 (no integrated 3.5mm jack). While you can’t get the 1697 part to work in a 1708 and vice versa (not that you’d want to willingly use the flimsy 1697 version of the part), you can get it separate from the entire case, but you generally need to buy a part kit with the IR cover, sync button and trigger part because almost nobody sells it piecemeal - it’s also a good idea to replace all of those for cosmetic consistency and the fact removing the cover can stress the plastics, but it’s not a hard requirement. If you’re gentle, it will be reusable.

In order to change it, you will need to follow this guide and remove the cover holding the trigger and sync buttons on to get to the part. It may be molded onto the replacement - in which case, you will need to play with the adjustment a little bit to get it right but that may not be a problem on the 1708 since it’s designed as a split part on the factory sealed controller. The part is easily found on eBay. I don’t recommend used OEM parts as the factory spec plastic is too fragile and will break again.