Peeling bark

[tacks Y]

I have some yellow birch that grew on old stumps, the stumps are gone now and the roots spread out. They have a wide Y look 5' or so apart. I want to saw the trees at 6' tall cut the roots at the ground then try to split or saw in half. I plan to stand them upside down and use as a shelf bracket, just screw to the wall. I am thinking I want the bark off, so will they peel better if I wait to saw them down in the spring? Or saw now and peel later?  Thanks