I just thought of something......

Have you done T-tail with flying stab before? (does that plane have the flying stab? or a fixed stab and hinged elevator?)

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Lets assume its a flying stab:

Why have you got 2 bellcranks?

The pushrod would go from the servo to the first 90. Then straight up to a clevce with the pin driven out or a brass tube soldered on and flattened and drilled

The flying stab pivots on the appx 25% line rod.

There should be another rod between the 2 flying stab halves that travele in an arc in a slot. That rod captures the drilled tube (or modified clevice). You get a VERY good loction to connect the pushrod at NO weight cost from having the control horn. (and the horn would be external... and thus adding drag...) you elimnate the second bellcrank (and its weight... and its control lnkage slop...)

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Did I uncover the reason for your binding too?