[Will a crankaroo work with one of those on there?]
Mine is a converted Sidewinder by Parker :
http://www.parkerbows.com/pb/2007/crossbowacc.html ( I just shimmed the inside of the stock bracket, added a peg that fits into Excal stock). It works perfectly fine, no interference whatsoever, Ischa. Don't have access to a Crankaroo but it seems it functions the same.
Cheekpeice would not be compatible with Ten Point's AcuDraw (as installed by Moon) not enough room for both.