I have realy only had first hand experience in maceration with old dead rotting skulls so it wasnt fun or easy at all!
Its stinky, messy, toxic, it didnt come out as clean as boiling or flesh eating beatles, its stains the skull and it takes FOREVER!!! I have done a little more research on the subject & believe the staining might have been the cause of sitting out in the weather for up to a year.
This is how I do new freshly killed deer skulls.
After skinning & removing what you can of flesh & brain matter boil it lightly, remove all remaining bits of flesh with a wire brush then pressure wash it, let dry for a day or two then hit it with peroxide avoiding the antlers if any, wash, glue back in the teeth clear coat & done!