Hi Dave;
      What kit are you building? I have a couple of "after market" kits but haven't built any yet. On the Sterling kits I have built, which has no plans, a degree or two right thrust, one degree downthrust, and one degree positive on the stabilizer.  I set all my models up this way. Got this from an old article in Stunt News that Bob Whitely wrote called, "Things That Always Work."  And I use little to no rudder offset. All of these help counter P-factor and torque, and some other natural tendencies that powered airplane encounter. I install adjustable leadouts also and a tip weight box.
     Type at you later,
      Dan McEntee

   I see the name Rigotti and keep wanting to type Hi Crist!

   Hi DAVE!!
   In Whitley's article, and it's been a long time since I read it, he describes that an powered airplane's natural tendency at zero-zero settings is for the nose to rise, and that is what the down thrust counters. At that time, left handed props were not in use for stunt, so no mention was made of them. But I would imagine that the same down thrust be applied even for a left handed prop, and you might not need the right thrust, or as much. The left handed prop thing for electrics has been discussed some, as guys were finding trimming issues that they had never seen before, at the same time they were finding out that electric model needed a more forward balance point. I haven't made the change to electric so have no experience with running them, but if memory serves me correctly, some were reporting that they didn't seem to be experiencing the expected effect of a left handed prop. My own uneducated wild ass guess is that any effect from the left handed prop may be getting mitigated by the mass of the motor spinning in that same direction. I got that idea from watching a TV show about snipers and the description of what was called spin drift. Whichever way the bullet was spinning from the rifling effect, the bullet would drift in that direction and they have to account for that when aiming. That motor weighs upwards of 5 ounces, correct? That is a lot of spinning mass.  I have one of those big Ringmaster kits also and will have to get to it one of these days.
  Type at you later,
  Dan McEntee

I second the recommendation of slight down and right thrust on the engine and a 'hint' of positive incidence on the stab.  About 1/8" offset on the rudder.

I've built dozens of Ringmasters over the years and the only one which flew worth a darn was one I 'blueprinted' rather than building it as it came of out the box.  I also slowed that big elevator w-a-a-y down.  They stall very easily with that thin wing.