Ted, sorry I was probably a little vague, I've added a little bit of positive incidence to the stab, as per RJ Whitley's things that work for stunt article.
It would be less than a 1/2 degree, about 1/32" height difference from the leading edge to the hinge line (3")
I'll futz around with the handle spacing to see what I get get sorted, prior to surgery.
Randy, I did have adjustment in mind, and did acutally build a removable tail cone, but after I found that the mounting pins were fouling the pushrod (I made the fuse too narrow to get it all in, silly me!) I simply glue it on, but it would only take a few slices to get at it if need be.
Greg, Don't take this the wrong way. I just need to know precisely how the stab incidence change was accomplished and in what direction. The reason I ask with such specificity is that Positive incidence in the stabilizer/elevator is more likely to make the ship turn more briskly on outsides...not insides. Positive incidence in the stab requires that the "leading edge" be raised in small amounts thus making the "neutral stab/elevator") at a positive angle of attack with respect to the wing (and, if you don't build in downthrust like RJ also--correctly in my opinion--advocates) and the thrustline.
If you've, in fact, built in the positive incidence properly and are experiencing more responsive inside than outside turns something else is haywire either aerodynamically or with the control system. I hesitate to raise this once again but...if you fly with the "relaxed/tilted handle" in level flight you might find the best solution is to get your handle more vertical at neutral which will automatically improve outsides vice insides.
Check to make sure your flaps and elevators are neutral at the same time and, if they're not, let me know which way. If you get more flap relative to elevator in one direction that will make cornering less brisk in the direction that deflects more flap. If that's the case there is something improper in the internal control setup, allowing unequal deflections inside versus outside.
As others have suggested, unsealed hinge lines can result in more effective flap or elevator in one direction or the other if the gap increases in one direction and closes in the other. In your case if the elevator hinge line closes with up control and opens with down the tail becomes less effective in outsides and will require more deflection to obtain the same rate of turn. If the flap hinge line opens up in inside maneuvers and closes in outsides you will have more negative pitching moment in the outsides fighting the ability of the stab/elevator to pitch the airplane in outsides. the solution is to seal the hinge lines so that there is no change in the gap.
I am not a fan of biasing the handle except in the grossest conditions where the airplane can't be trimmed aerodynamically to fly uniformly inside versus outside. FWIW, I've never had a stunt ship that, when trimmed, required any significant, measurable difference between up and down line spacing at the handle.