Getting primer off original paint

Whats the best way to get rid of rattle can primer/ paint thats over my original paint? I'd like to see if it's saveable or not. There's currently 12 different colors spotted all over but the back of the cab is a beautiful mint green.

 

easy-off. grocery store. yellow can.

 

I used a sos pad to get it off glass and chrome, worked great....

 

I'll try oven cleaner, thanks!

 

Here's what I'm working with

Posted using the Full Custom H.A.M.B. App!

 

Posted using the Full Custom H.A.M.B. App!

 

The original paint is under this primer.