Yes, you need to support the engine and remove the rear mounts and bolts. You will also need to remove the fluid coupling, it is mounted to the crankshaft with 8 bolts. Be ready when you pull the fluid coupling, its heavy. Once the fluid coupling is removed the seal halves can then be replaced.
After second thought you may be able to remove the fluid coupling after pulling the transmission with out pulling the bellhousing, no 100% sure if there's enough room or not.