To further clarify, each of the lenses is unique. The same barrel is used with five locations for 19°, 26°, 50° and two lenses making 36°.
The Colortran 5/50 (and from the 1980s MiniEllipse) line of ERSs exploited the formula EFL = (f1 * f2) / (f1 + f2 - d) [where EFL=Effective Focal Length, f1=Focal Length of Lens1, f2=Focal Length of Lens2, d=Distance between Lenses.]
to allow different effective focal lengths from the same two lenses; a principle also used by Zoom Ellipsoidals.
It will make a difference - it will ruin your fixture. You won't get another degree measurement, you won't be able to focus your fixture - it just won't work correctly anymore.
To expand a little on the last point, the lenses are all different sizes and will only fit in one of the five slots, making it impossible to move them from one point in the barrel to another.