I found this at a relative's house today. It was my uncle's Fender Mustang from the 60's. Can anyone give me some information?

What kind of info do you want? You already know the model. What is the serial number?
is it yours now?

If it is, Congrats!

For more information you can run the serial number (should be on the headstock) through some type of Fender search engine thing.