Honestly, I don't think it is. I haven't changed it yet, but it doesn't look to hard. Just get the right tools and definitely a Motorcraft rear main seal. I have heard bad things about using off brand seals
To remove the old seal the only way I've seen is with a couple of old screws or a small pick like from harbor freight.
Just be very careful that you don't scratch the crank as that will cause the new seal to not work properly.
Rear main seal tool
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Rear main seal
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We pulled our engine to replace the timing chain cassettes and chains. Figured we might as well replace the rear main seal while the engine was out.
Good luck!
If the links don't work just look it up on eBay.