Hi Kevin, thank you for reaching out. The hinge orientation of this item is similar to the original part. You can use this link to continue ordering the part at 42% off the regular price today: https://www.carparts.com/fuel-door/key-parts/fit0852029?can=CPAP3648_CSQA_20230102 I hope this helps. Enjoy shopping.

no it set up for one way only the door should open towards the driver door if flipped to go toward the rear of the vehicle it well not work?

Hi Ronda, I'm glad to assist you. We don't have the exact diameter, but this is a direct replacement for the original ones installed on the 1988-1998 GM full-size trucks. I hope this helps, and if you're interested in this fuel door, you can click on the link below for direct ordering to take advantage of our ongoing sale and limited stocks. Happy shopping. https://www.carparts.com/fuel-door/key-parts/fit0852029?can=CPAE1047_CSQA_20220810

6 inches

Hi Gloria, I'm glad to help you out. Yes, we do carry those types of fuel doors but, I could not give a recommendation since I do not have the vehicle information to work on. You can do a manual check for the availability and fitment - On the Homepage, please enter (complete) your vehicle’s year, make, model, sub-model, and engine size. Type the part's name in the search box. Once your application is selected, you’ll see a “Guaranteed to Fit” badge if the part will fit, and we recommend that you also double-check Your Vehicle Fit Details as well as the Vehicle Fitment Information table on the product page. I hope this helps. Have a nice day.