I myself would drop the rear drive shaft out. 2x or 4x4 towing on a 2wheel dolly. on a 2x towing for sure will kill a trans in N while towing short or long distance at speed with the shaft spinning.

you can leave trans in park and shift t-case to N... on a full time rig. it will let the rear driveshaft/axle turn while the front does not. it will be spining the t-case differental/spiders and rear output shaft.

if it is part time, same thing shift t-case to N and let the rear shaft/axle only turn.

short distance/low speed should not be a problem.

but IMHO...5mins droping a shaft is way cheaper than a trans rebuild..why risk it?

plus it is less drag just pulling the weight and only turning the rear axle on truck being towed.