I'm in the process of cleaning my whitetail skull but I had my mule deer and antelope skulls cleaned for me by a fellow out of Wyoming. He charged $65 each and had them done in less than a week. Not sure how exactly he does it but he had well over 100 skulls in pots of one sort or another from some monster elk to longhorn cows and even a giraffe! If I was local to him I would just pay the $65 instead of messing with it. I can't imagine paying $250 to have a skull cleaned. Around here you can get a nice shoulder mount for $450.

Here's the skulls that I had cleaned.