Awesome stuff. Your dad is a true man.
My dad struggles with a ton of physical issues. Amputated leg and collapsing vertebra due to a motorcycle/deer crash among other things. Built a blind for him this year. He hasn't been able to get out to it this year but I'm hoping next year he'll have surgery on his neck and leg and be able to put a couple of days in. I remember back when I was a wee boy he went out two days after carpal tunnel surgery on both wrists and shot a deer for the family(we were pretty poor back then and it was needed). Quite the role model.