I am looking for a little help figuring out the rest of this ribbon stack. This is from a photograph of my Grandfather. Any takers?

Can't quite figure out #13 but this is the order of precedence I have so far.

Legion of Merit Medal Ribbon
Meritorious Service Medal Ribbon
Air Force Commendation Medal Ribbon
Air Force Outstanding Unit Award
National Defense Service Medal Ribbon
Korean Service Medal Ribbon
Vietnam Service Medal Ribbon
Air Force Longevity Service Award
Small Arms Expert Marksmanship Ribbon
Republic of Vietnam National Order Medal 5th Class Ribbon
Republic of Vietnam Gallantry Cross Unit Citation - AF/N/MC/CG Frame
United Nations Korean Service Medal Ribbon
Republic of Vietnam Campaign Medal Ribbon

Did you try using one of the ribbon/rack builders to identify them, like medals of America?

You sure make a guy feel old, but I am a grandfather.
#12, Vietnam Cross of Gallantry, was worn on my right side rather than in the rack.
Your grandfather's rack is quite impressive, Chief! Sorry, but I can't identify those that are in question.

I'm not certain if #11 is the Armed Forces Expeditionary Medal.

13 - https://wikivisually.com/wiki/SICOFAA_Legion_of_Merit_Medal

#13 looks like the System of Cooperation Among the American Air Forces award of their Legion of Merit, which of the three grades I can’t tell. It’s similar to the inter-American defense board, or the multi-national observers medals.

https://en.m.wikipedia.org/wiki/System_of_Cooperation_Among_the_American_Air_Forces#Awards

https://en.m.wikipedia.org/wiki/International_military_decoration_authorized_by_the_US_military

Yes, I know Wikipedia isn’t the best resource, but it’s the quickest for this post.

#6 Looks like the Korean Service ribbon that would explain the star on the National Defense ribbon, two separate wars.

I think 13 is purple hart 2nd not sure. good luck

Without the colors I could never get close

6 - Korean Service Medal