How to set the canonical orientation of a prefab?

I am using a 3D ship model that I stole from the Unity Shooter demo. In this 2D demo, the game is set up in the X-Z plane.

I have exported this prefab and imported it into a new Unity project set up for 2D. By default, Unity uses the X-Y plane for 2D.

When I attach a RigidBody2D to the ship and try to torque it, it rotates on the wrong axis (head over heels).

How do I "pre-transform" my prefab so that Y+ is the front of the ship instead of the bottom?

 

Note: I am not asking how to transform the ship. I know that by rotating by X = 270 I can get the ship to point forward. However, the RigidBody2D.AddTorque function assumes rotation around Z.

So my ship does a barrel roll instead of pivoting.

 

Anyone? Not being able to do a simple rotation in Unity makes me feel stupid.

I've discovered the "Apply to prefab" menu item, but it is disabled for me, and so maybe not useful for baking in a rotation.