I assume you are working on your 2016 tax return. With the exception of carry over losses if you sold the property at a loss, nothing concerning this would be reported on a 2017, 18 or 2019 tax return.
Your cost basis on the sale is the cost (what you paid) for the land, and that's it. The structure has been fully depreciated without a doubt. So your cost basis on the structure is zero.
Now if you did any property improvements *AFTER* tax year 1989 then it's highly probable those assets were not fully depreciated by the tax year you sold it, which was 2016 as I understand it.
