Yes. ERC will do it. You must insert the script, Poser will not convert the rotation channels for. Set all of your morphs to the closed position and create a Full Body morph. Make a note of the degrees of rotation. Save the prop file. Open it in EditPad and copy the five lines for the ERC and paste them into a same location in the target rotation channel(s). The DeltaAddDelta for the rotations will probably be 1/degrees.