I have been experimenting with LED replacement illumination in all sorts of applications in airplanes, boats, tractors, autos, etc etc and found that interchangeable, simple-replacement LED lamps are usually NOT the solve-all/end-all solutions people hope-for.
INcandescent lamps have a wide-spectrum of light energy they throw which, although wasteful of energy such as heat, usually fill-out the objects being observed. Thats a way of saying that LEDs may put out more measurable lumens but they dont always illuminate because of the narrow spectrum they emit.
Im not familiar with the B7800 OEM headlights, but the OEM headlights of my M4700 Kubota positively SUCK. They are dim-yellow and the only thing they are good for is to GLARE the backside of the Front End Loader bucket, fork, or frame, depending upon what tool is loaded. On top of that, they are a proprietary bulb which costs ridiculou$ly and is not commonly available. (The headlights are mounted down low as if no FEL was ever planned for the tractor, so the FEL blocks all forward-illumination of the lights. The local Kubota-dealer told me the reason they were built that way was because that was as high as the Japs could REACH!).
I solved my headlight problem by mounting an LED Light-Bar on top of the radiator-guard which places the HUGE amount of light above both the hood and the usual height of the FEL. Its the CATS MEOW for seeing at night!