What should I do with my grandfather's WWII manuscript and time line of his 35 bomb runs?

Check to see if any are still alive. Get permission and publish it as a bio

Either publish it or give it to the Veterans Museum!

This aerospace historian recommends scanning it for your own files, then considering whether there might be an appropriate military or aviation history museum that might want to add that journal to their collection. For example, the Eighth Air Force is headquartered at Barksdale AFB, LA. Therefore, it’s possible that the Barksdale Global Power Museum might be interested. Feel free to send me a private message to follow up and I might be able to help you. Finally, please be patient with us because we’ll be responding to routine inquiries very slowly during the COVID-19 pandemic.