1988 D Lincoln Cent DDO Or Special Mint Mark And/Or DDR

This 1988 D Lincoln Cent might be DDO or it might have something special going on with the mint mark. What caught my eye was the two 8s, mint mark, and then LIBERTY appeared to be spreading to the East. I tried to match it up to a variety, but there are quite a few to go through, so I thought maybe someone out there is familiar with what it should look like if indeed it is a DDO or special mint mark.

Also, I thought EPU looked kind of thick and so I thought maybe it was a DDR, but likely not if it is a DDO or special mint mark? I got more interested though when the Memorial showed some signs.

I was hoping someone familiar with the names of the Memorial parts might tell me what the decorative ridge is called that sits on top of the front edge of the first roof. I was exploring Memorials under the microscope after coop included a graphic for me in another thread, and found something odd on that ridge that might be doubling, or maybe not. I included a pic from the microscope and would like to know if that is how the design was created, i.e. the doubling might actually be two ridges in the design. Maybe somebody has a good HD close-up pic from one of those high powered microscopes?

Thanks to anybody who can help. I really appreciate it.