Looks to be strike doubling, you can tell because of the flat and shelf like appearance of the doubling coming off the devices. But check the reverse, there is a transitional variety with a "flared G" in the initials. It's what the error guys call the "Reverse of 1989", there will also be some minute die scratches on both sides as well.
This link my help?? below is JW new finds http://doubleddie.com/12201.html I am not sure if extra ear 1988 was a P or a D? this is the 1988-RD http://www.lincolncentresource.com/Featured/1988RDV6.html