I have a 1985 KLR250 that I wanted to add an LED headlight to. I ordered one off eBay, I expected it to come with 4 mounting holes on the back that I could use, but it didn’t, so I had to get creative with installing it.

You will want to press the led headlight into the existing bracket as far as you can. I had to take a file to some spots on the light/bracket to make it fit all the way. Mine is friction fit into the metal bracket tightly. I used the screws that came with the original light.
I’ve done a few rides with this installed, seems to hold. I may revise it by adding a spot for a nut to make sure the screw stays in place. Right now it threads into the plastic just fine, but I have some tape over the screw just to make sure it does not vibrate out.

I used PETG, 3 walls, 20% infill. You might need to tweak it for your specific light.