The fix is to reduce the right thrust on the engine by inserting thin flat washers under the right-side screw that affix the engine mount to the firewall (you can also use a popsicle stick, or make a ply wedge).

The built-in right-thrust is correct for 1/3 - 1/2 throttle cruising, but is excessive for full power operation (like take-off). The Nexstar flies perfectly well with no right thrust at all.