The only "filter" is the screen in the bottom of the glass bowl on the fuel pump. Most added a filter right at the carburetor. KW has the period correct NOS filters that a lot of dealers and owners installed. https://www.kaiserwillys.com/nsearch/?q=fuel%20filter
On my carb a WO, I use the metal one. It goes right into the carb with a 1/8" pipe close nipple, then the original fuel line hooks right up. You remove the fitting from the float bowl and screw it into the filter inlet. I am not sure how it sets up with your carb. You have an F head '65 right? You have a YF Carter and a different fuel line set up. Any good filter between the pump and the carburetor will greatly improve the reliability. The Carter's have a very touchy idle circuit. The smallest particle and the idle is a mess.