OK, how hard is this for someone who is pretty, well, "Handy"? I was given an old (relative term) SB1 .410. I have a good barrel with a heavy coat of rust outside, same with the action, no forend, a butt stock that was cut off with a chainsaw, and a trigger guard that looks like it was chewed off with a pair of side cutters. Everything else I can do in my sleep, but I have never messed with the inner workings of a handi. Could someone please give me a walk through on this?