As far as special tool go I think you might want to check into a fly wheel turner. And if I may add, it will probably be in your best interest to take the engine and tranny out together to do this job.
When I was stripping my 55' down it was about 100X easier to work on rather than being under the car. Some petty inexpensive ways to do this also would be to buils an "A" frame out of scrap 4X4. I found this out after I spent 300 bucks on a cherry picker and an engine stand.
About the flywheel turner though, I know the fly wheel bolts up to the torque converter and the crank shaft if I'm not mistaken. The tool keeps the fy wheel stationary while you undue the bolts: In lue of a flat blade screw driver, bloody knucles, and a lot of cuss words.
I'm pretty sure that is one tool you will need and can also pick up at the local auto store.
After removing the bearing cap, use a small punch to tap one side of the seal. Do this very carefully, so you do not knick or scratch the crank journal. Some engines with high mileage have a varnish build-up under the seal that can make it extremely difficult to get the seal to start moving. As a last resort, I have loosened the other main caps trying to take pressure off the rear seal. After the old seal is out, double check the orientation of the new seal. It's too easy to put it in backwards.
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