I can tell you, you will enver have normal stereovision. That is impossible. Steresovision isnīt a "eye- thing" but a "brain- thing". Your brain takes the images from each of your eyes an puts it together. If it doesnīt fit properly, your brain disables one image. Many people then get a normal functioning eye and a very weak one. in you case, you had an operation (as i had) when you were a child. cause of that, your brain could supress a part wthout supressing the whole eye. usually your brain developes stereovision in the first 2 or 3 years in your life. now its to late. operating now could even worsn your binocular vision.
I was lucky that i coul develop a bit of stereovision.
Ask the guys in gatwick what you can do about your eyes.