Transformer question - ground ?

Hi all,

I have two transformers from old Epsom printers.

each has a 28 volt and 8 volt output, plus one ground that was tied to
the frame.

I really only need the 28 volts, (I'm assuming 24 under load) and not
the other voltages.

I think I would be fine tying off the 8 volts (5 under load??) but my
question is about the ground.

Should I bring that to panel ground/ earth ground ?

should I tie it off and not connect it ?

Any suggestions ?

dave