Hi there, yes its a big job! You have to remove the gearbox to get to it. Either take engine with gearbox out of the car, or lower subframe and tilt the engine to get it out. Its not impossible, I did it and I am not a mechanic, and if you are one, it should take a day. It took me about two weeks with maybe two hours every day!
I was able to replace mine in the driveway with "home made" special tools. The big one is a tool to suspend the engine to keep it in place after you drop the subframe. Mine took me nearly a month but I had a big job running out of town and it seems like it was raining every weekend when I got back home. In reality, 2 or 3 good days will get it done for a shade-tree mechanic.
While I had the transmission out and was getting the flywheel resurfaced I also replaced the rear main seal. The old one wasn't leaking but at 235 k miles I thought it would be a cheap preventative measure.