Clear the 2017 online tax return.  Click on Tax Tools.  Click on Clear & Start Over.

To complete a 2016 tax return using TurboTax you will need to purchase and download one of the 2016 desktop editions from this website - https://turbotax.intuit.com/personal-taxes/past-years-products/

A 2016 tax return can only be printed and mailed, it cannot be e-filed.

It will not allow me to 'Clear & Start Over' because it has already been 'registered'. Looking to amend the 2017 return but it says that the paperwork is not yet available.

You do NOT amend a tax return that has not been filed.  You just correct the errors on the tax return before filing.   Go through the sections of the return where you entered data and remove or delete the data.  Once you are ready to enter the correct 2017 data you can continue this tax return for 2017 since it has already been registered.

The status of my 2017 return is “FILED”. I am not able to make any edits or changes to this.

Then all you can do is wait.  The IRS will not be accepting any type of 2017 tax return until January 29, 2018.
An e-filed tax return cannot be retrieved.  If the IRS rejects your tax return then you can make the needed changes and re-file.  If the IRS accepts the tax return, then you will have to file an amended 2017 tax return to make the changes.  An amended return can only be printed and mailed, it cannot be e-filed.  The IRS will take up to 16 weeks to process the amended tax return.
You will receive an email from TurboTax soon after 01/29 informing you if the IRS has either accepted or rejected the 2017 tax return.

Sounds good. Thank you. Hoping that they will catch that it is a 2016 W2 and they will reject it!!!