Beattie Intenscreen installation on Linhof Tech III problem

I purchased a Beattie Intenscreen and installed it according to my best interpretation of the directions on my Tech III: protective glass plate closest to my eye, then the intenscreen with the matte surface facing the lens.

I then shot a sheet of film, using for a subject a meter stick angled away from the lens plane, focused at the 24" mark on the meter stick. The developed sheet is actually in focus at the 28" mark, leading me to believe that the intenscreen portion may be in backwards. Does this sound like a logical conclusion?

Thanks in advance to anyone who can help me.

Dan

Normally, when installing a fresnel lens into a back that was designed for just the groundglass, one keeps the groundglass closest to the lens and installs the fresnel on top of the groundglass: lens - groundglass-fresnel-photographer.

Doing it differently puts the focusing out of registration with the film holder. If you installed your interscreen between your lens and the groundglass, your focus will be off.