No, it's not hard.
First, jack the car up and put on jackstands.
You will need to loosen the bolts on each end of the mounts, then jack up the trans enough to take the weight off the old mounts. Put the new mounts in, start the nuts that hold them in place. Lower the trans and tighten the nuts with the weight of the trans on the mounts.
Hope this helps,
vince