[High5er]

I previously had a Silverado 2500 standard bed and Cougar 364MBI that I towed with an Andersen hitch. I'm not sure if that's what you mean by 'fixed' or if you have something similar to the fixed B&W Companion hitch, but I could get slightly over 90 degrees with the Andersen. It absolutely depended on the receiver/adapter orientation on the pin box. When it was initially installed, it was terrible. I could get maybe 60-70 degrees because they oriented the adapter backwards. All good once it was installed correctly.