Measuring a divided differential voltage into a single ended DAQ
Think about this circuit: -

In the 2nd circuit I've removed resistor component values because they are not correct. I've also removed the op-amp type number because it is not a rail-to-rail type. I have also removed reference to +/- 5 volts on the power rails because not even a rail-to-rail op-amp can ever produce an output voltage of +/- 5 volts from +/- 5 volt rails.

You would choose R1 and R6 to have the same value
You would choose R5 and R7 to have the same value
You would choose the ratio R1/R5 to be big enough to cope with the +/- 60 volt input signal
You would choose power rails of +/- 10 volts and have many op-amp options open to you.
You WOULD NOT connect measurement ground to machine ground

Protecting the DAQ input

Use a 100 Ω resistor as shown and connect the output (aka measurement voltage) to the DAC with an additional pair of 6.8 volt zeners in series opposition to measurement ground. The value for the zeners depends on the DAQ limits.