You can overwrite your saved stuff in game...but why not on the website? I mean...I don't wanna have to constantly reupload my ships, my planes, my ships, my cars...MY SHIPS!!!
Example: When you click Share Aircraft, it says something like "Would you like to upload a new aircraft, or overwrite an existing upload?"...something like that, then brings you to that screenshot and description screen.
Cause some of my stuff is quite improved...but I don't wanna flood my list with the same stuff over and over again, or remove them...then reupload them.
...MY SHIPS! (lol)