is it possible to flip the image on a tv somehow?

I built a projector with an old CRT television, a box, and a projector lens. The only problem is, the image was reversed both vertically and horizontally. I got a tip to either flip the tv upside down, or change the four wires inside a certain way (red to blue, and green to yellow, and vice versa). I did that, and it fixed the upside down image, but the image is still reversed from left to right. Any ideas on a few wires i could change around to flip the image from left to right? Any help would be greatly appreciated, and I already know about the warnings, precautions, etc. when working on any type of electronics (especially CRT monitors and televisions), as I am a computer tech...just not very informed on television repair, and modification. Also, it was recommended on a website somewhere to attach a mirror to my projector, but that's not a solution, just an eyesore. Thanks again for any help anyone may have to offer.