I would always take about 3-4 neck measurements when I got the head in. Assumingthere was enough neck left. That gives you a place to order the form from. Without those measurements you are mostly blind. Having the hide tanned will allow it to only just barely fit what it was. You cannot give it more like dry preserved hides will stretch.

One other thought -- I've shot a bunch,seen a bunch more shot and measured a bunch. Seems that when the deer is laying on the ground the neck seems lots larger as it goes to an oval shape more than a rounder shape. So the hunter sees an optical illusion. Its wide, but not thick.

FWIW on my deer, as I measure them, I have them always to within an inch in neck circ. of what they were one way or another. Most folks can't tell the difference between 20-21 inch necks. In fact its hard for me too. And I'd rather work on a form that fits as one thats too large or too small is about the same in the problem areas.

Other thought is that you have to have a source of forms that offers the different necks. IE if you try to order strictly off the eye to nose measurement you may only get one neck size. McKenzie offers many differing neck sizes from pre rut, normal, semi swelled and full rut all in the same eye to nose size. You might check with him on that.

In all my years, neck size was the most complained about issue and it was advanced due to the local taxidermists using dry preservative and stretching the crud out of the necks along the way. Never mind about the cracks in the mounts years later due to this.

Many issues here.

Jeff