You indicated selling late 2019. You correctly read that they need to sell by 3/1/2019. It is past that date, so there would be no partial exclusion. Just do a sale of a rental. I assume you are depreciating, so do the sale through the depreciation screen.
https://accountants-community.intuit.com/articles/1857451-individual-1040-sale-of-property-used-as-a...