I took some measurements this morning and discovered that the plane apparently has a considerable amount of LEFT thrust built in.

Not only are the engine mounts off center on the firewall and mounted about 5mm or so to the LEFT of the centerline, from the tips of a 12 inch prop to the wingtips, the distance is almost 1/4 inch GREATER on the right than on the left, indicating a lot of left thrust.

My plan for tonight it to remove the engine and mounts, and shim the left mount with washers until the thrust angle is at least neutralized.

YIKES...