“its a single rotation about a vector defined in the quaternion. Thats all it is”
Right, simple for you to “get”, but not to most people. That’s where the subjective difficulty of mathematics lies. Objectively, if we were all computers, it would all be equally simple, but we are not computers.
Easy shit:
Quaternion.eulerAngles(x, y, z)
Quaternion myRotation = Quaternion.identity;
myRotation.eulerAngles = new Vector3(150, 35, 45);
And no Gimbal Lock