How to rebuild door threshold when using self leveler to outside door

Question

I am pouring self leveler before putting in new floors. I have to raise the floor 1 inch. How should I rebuild the threshold of the outside door?

1. I thought to just use self leveler all the way to the outside of the door then cut down the door.
2. I thought to build a small concrete threshold pad to the outside then pour the self leveler up to the new small concrete threshold pad, then cut down the door.
3. I thought of finding a raised threshold that was a perfect fit, then pouring the self leveler to the new threshold then cut down the door. I am not sure if there if something like this exists though.

Any thoughts would be helpful from experienced contractors.

Here are some pictures and video link (Starting at the outside door where I need to redo the door threshold and ending with the part of the house that I need to bring the floors to be level to)

My unlevel floors video