So, I got a set of flea bay and now wondering if other guards attach to the light in a different way. These seem to use the existing hardware from inside the jam of the tailgate and then double stick tape to the outside.

Do any bolt on or clamp somehow from the outside and the inside?

How to OEM attach?

 

I believe they all attach the same way. I've seen the actual HUMMER ones and they are the same. There is really no way to attach them on the outside. I bent my tabs in a little so they sat more under the lip of the tail lights to secure them more. I put 3M double sided tape on them, the gray stuff but didn't remove the backing to the truck. It provides a small cushion so the tabs don't scratch the paint and the lights holds the outside of the guards in place.