engine must come out
First time I had to do it, took about 4 hours to get engine out
I rode the sled the next day
Now it takes alot less time, these are simple to pull the engine on IMO. Make sure you have Ford fuel line tool
It takes about as much time to clean and drive in the new seal, as it does to pull engine.
Be careful seal is delicate / two piece and can come apart if you don't install it correctly.