For an 8" spin doctor you'll typically run the fly about 18 to 26 inches behind (22-24 inches is probably most common). I like to attach the fly to the hole on the "more action" side (the hole across from the fins not right behind them. When I run them off the downriggers, I use a 15 to 20 ft lead past the release.
For spoons, I love the Moonshines, but I would suggest picking up a few non-glow finish spoons as well. I'm not sure what other brands the Ontario guys use as I fish Lake Michigan, but did well with the magnum sized Silverstreak Blue Dolphin last year. I also did well with a variety of Dreamweaver Superslim spoon (pretty much anything orange for steelhead) and a variety of greens and yellows for salmon and purple or black down deep (70+).