I've done a few european mounts and here's the easiest way I've found without the need to use any chemicals. Skin it down and remove as much tissue and fascia along with all the brains. Use a large metal tub or pan on a propane campstove and bring it to a boil outside and out of the wind. Place the skull in the boiling water for about ten minutes submersing it just to the antler bases. Remove it from the water and pick off any remaining tissues that have loosened up. Use a forceps and remove all of the nasal contents. All of the soft tissue and much of the thin plate bone in the nasal passages will come out. Tedious, but you have to get all of it. Re-boil for another five to ten minutes, then use a high pressure washer to clean off any remaining tissue. I strongly suggest using a do-it-yourself carwash, as it is quite messy and the hot water and soap greatly aid in doing a thorough job. Blast inside of the brain cavity and much of thelining will come out as well. Later, you may have to spend a bit of time cleaning the thick fibrous tissue from around the antler bases carefully with a small knife.If you've done a good job, no bleaching of the skull is necessary.