Benjamin Trail NP collapsible stock build

I have a Crosman Nitro Venom, and a Benjamin Trail NP rifle. On the Nitro Venom i put a Vector optics scope on it, and it requires nearly 5 inches of eye relief. So that pushes the scope too far forward and gets in the way of the break barrel being opened. So I am modifying the Trails stock to accept a collapsible stock from the AR--15 style rifles so i can push my shoulder farther back and get the proper eye relief needed. Once I figure out how to post pictures I will get them up here.