WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
Remove the fuel injection fuel feed pipe bracket bolt (4).
Loosen the 2 nuts (2, 5).
Remove the fuel injection fuel feed pipe (3) from the fuel rail (1) and from the fuel injection pump (6).