Instructions for using Sinar 6x7 film back?

Hi,

I'm hoping someone out there uses a Sinar 6x7 film back for 4x5 cameras. I just acquired one, but (to me) seems a little complex to use.

Does anyone have instructions?

Sinar do not list anything on their web site, and google search is fruitless.

Thanks in anticipation.

Regards

Steve