"LaTriker"....Your posts are a little confusing. It's unclear if the picture posted is your generator or one on another coach. I have had two 8K Onan generators over the past ten years and the fuel filter is as shown in your drawing. It's hidden behind a metal drop down door.
If yours ends up being the one in the drawing, there are a couple of tricks to change them. First, you SHOULD use fuel filter wrenches like this to loosen the fuel lines. They are very soft and can be easily stripped if you use a regular wrench. I don't recall the size, but I know the two lines are different, possibly 1/2" and 9/16".
When doing the filter change, have a plug ready for the fuel line. If you've ever cut the tip off of a tube of silicone, something shaped similar to that works as a temporary plug.
Before you loosen the two fuel lines, tie a rag around both your wrists. This will prevent fuel from running down your arms.
Open the trap door under the generator, loosen/remove the center hold down bolt on the filter and then remove the fuel lines. Have the new filter within reach. You can either plug the one fuel line that is dripping and take your time, or quickly get the fuel line started on the new filter. There isn't much room to work, so be careful you don't cross thread the lines. Reinstall the filter and hold down and THEN snug up the fuel lines.
Side Note: NEVER use a trouble light when working with fuel under a vehicle.
Don & Mary
2019 Newmar Dutch Star 4018 - All Electric
2019 Ford Raptor Crew Cab