Spare size?

How much smaller in diameter is the space saver spare in an E-body compared to stock tire?
I have a nice spare from a new car that is ~1” less diameter compared to what I drive on.
Any issues damaging the Dana power lok with 2 different diameter tires?

It’s not a good idea. It’s like driving your car in a constant circle...LSD’s don’t like that.
But if you absolutely have to.....

1). Keep your speed a low as possible, the rear is generating heat, and speed makes it worse,
2). Be as light on the throttle as possible...the forces on the clutch plates are FAR greater under high torque than low.
3) Keep your distance as short as possible,

I don’t carry a spare in my Cuda...I carry fix-a flat and a repair kit. A AAA card and a cellphone.