Unfortunately, not all of them were signed. I'll still attach them here - thank you to each redditor who made his 60th birthday all-the-more special:

u/bouncebackbelle - Your penmanship is extraordinary. Thank you for pouring such sweetness into your note.

u/kimmylubs - Adorable postcard and stickers attached!

u/orangewolpertinger - I had a fun time explaining to my dad what Humans of New York was.

u/English-Muffins - It meant a lot to my dad to read I'd said "wonderful" things about him - thank you.

u/green4thshift - Is it weird to say the front of the card you sent felt nice to the touch? Well, it did.

u/rosaliethayer - What can I say? The dog card and dad joke made him laugh. You were right on the money.

u/kittenscoffeecats - Your card was perhaps the cutest he received. Thank you for all of the bonus items!

u/pjaynes - My dad loves puns. Thanks for one!

no username ): - This sweet note came without a username attached - thank you, kind stranger!

u/SiamLinio - I think all of you knew dads historically love puns - this card was no exception. Thank you, haha.

u/LeeElla - The card itself and the seal were completely extraordinary. Thank you so much.

u/Maxmax09 - This card travelled all the way from France - you were awesome for using my dad's favorite car!

u/monxlix - Dubai?! Way cool.

I'll be going through these links to check they work and adding usernames in the comments within the next handful of minutes - thank you all so very much for taking time to spread kindness. It made a difference during a strange time in world history.

Edit: One of the usernames I couldn't figure out came forward! It has been corrected.