Heathkit impedance bridge model IB-28 manual needed

[HiFiCanada]

I have the Heathkit impedance bridge, model IB-28 and when I retire, I would like to use it and winding crossover coils just for my own use. The impedance bridge would be fun to play with and educational at the same time , something to do during my retirement years.
But I need the complete manual that explains how to use it. I have looked all over the net for quite a while, but no luck.
Does anyone have suggestions as to were I can find the manual?