To be honest, I feel kinda sad that he got rid of the arc reactor. I have come to identify that circular thing with Tony Stark himself. It's symbolic to me, much like Cap's shield and Thor's hammer.
Post the link to your gif, I'll do it for you. Or if you want to do it yourself, try this site
http://www133.lunapic.com/editor/
You have to save the gif to your computer/laptop first, then upload the image on there to edit it.