I have a Mule that I am having difficulty fitting for a collar. She has about a 4" wide band or crest on topline of neck so when I fit a collar that is the proper length there is a hollow in middle of neck under collar. To help this I use a pad I am using a 1/2" felt pad because it was thinnner than a deerhair pad because on top part of neck the collar fits snug. With the pad the top part of collar is too tight but without pad the collar does not sit agains neck in middle. As well she is a black mule and the hair on neck where collar sits is bleaching turning a slight red, I don't think these felt pads breathe well and I think it is getting too hot.? I have also wet this collar and then used it on Mule all day to try and conform shape but still not great any ideas would be appreciated. thank you