Please help me identify these stepper motors

I'm new to this and unfortunately, I'm trying to retrofit a
Bridgeport milling machine by changing the existing NC controller
with modern drives without any documentation or specifications.

The BP has NEMA 42 stepper motors on XY and Z axis. The motors weigh
a little over 19 pounds each. The eight connections are laid out in
two rows in the back. The motors measure 6 3/8" on the cylindrical
part and 6 7/8 including the square mounting flange. The existing
power supply runs about 62 volts DC. When I test the resistance of
one of the windings, it's so small, I can't get a reliable reading.
(I guess in a pinch, I can connect all the coils in series and
measure the total and divide by 4).

Any clues if this is one or two rotor (I read here that it's not a
good thing to disassemble stepper motors and physically check)? Any
idea what a reasonable current setting for the drives to try out the
setup?

Thanks in advance.
Jeff