Horseman Bino Mirror viewer usability? Diopter changing?

[Tin Can]

I just bought a 4X5 Horseman Bino mirror box viewer with some sort of OE stereo diopter.

Pretty obvious this diopter will not work for me.

I can't see much with it, or without the diopter.

Has anyone had any luck changing to a custom diopter for a Horseman Bino Mirror box?

[Tin Can]

I just tried using both an OE Horseman Fresnel with Horseman GG and Horseman GG without fresnel and the latter option is a little better.

I need to change BINO diopters and it sure appears I need new spectacles, doing that Tuesday...