RZ67 Teleconverter on RB67 questions

Mamiya RB67 & RZ67 Users

I came across an article about modifying an Rz67 1.4x teleconverter for an RB67

MAGNAchrom: Modifying a Mamiya Tele-Converter 1.4xRZ to fit an RB67: The Alternative Journal of Medium and Large Format Photography

This was done for using on a ProSD, not ProS which I have

What I am looking for is the dimensions of the body facing throat on the RZ67 Teleconverter, OD/ID.

The conversion seems pretty straightforward but the fit on a ProS body is in question.

Anybody out there that could make this measurement & respond?

That would be great.

I know some will why not use the 3rd party 2X converters from Kenko/Vivitar but I want the 1.4x factor if I can

Thanks