Level of difficulty is easy. Removing splash shields is optional, but easy. 4 bolts holds the crossmember to the frame, one bolt per motor mount to the engine/tranny, crossmember is now free, two bolts hold the rear mount to the crossmember, swap it, two bolts hold the front mount to the block, remove it, swap it, then put the crossmember back. Done.
That's if you are swapping mounts. If you want stiffer mounts I highly recommend homemade ones like I made. Trying to find the post yesterday that I made with the pics and info but I am unable right now...