Re: Not sure what this is called
from the muskrat i have worked with the guard hairs were just to short for a dry fly tail. if the guard hairs on the skin you have are longer and measure about 1 1/2 the length of the hook shank, then by all means use it.
same thing with the wing.
there are other materials to tie dry flies but use what you have on hand.
Poor quality materials are destined to discourage beginner tiers and cause greater expense when the time comes to replace them.