lhommedieu, I have done a few of these. I have done with skin on and also skinless. I prefer the skinless. I brine mine over night in a salt/brown sugar brine. I try to keep my smoker around 200 degrees, but the best one I did, the smoker got to around 250. It had more of the fat ooze out, but I did not care because it was so good.
I do not mop during the smoke, and I also take the IT to 160 degrees even though USDA says it is done at 145 degrees. I think it gives it a little more "crust" or bark on the outside.
The way you describe with it being darker with the outer layer layer crusty, is how it turns out. I have not put out the sour cream and chives, but have just put a hunk on a cracker.
Good luck with this and report back.