can I make my own decal

You can get a clear (mylar?) decal material (8.5x11) for inkjet printing of window decals from either Xerox or Avery at Staples office products.

Take a jpg photo and use graphics software to convert to either gif or png formats. Then use graphics software to make the background transparent - if you want that effect - otherwise stay with jpg. Print with color inkjet. Apply to surface and clearcoat.

I have done something like this for an inside window decal but no clearcoat. The "adhesive" on the material is not strong at all. In fact a decal is very easily removed from glass w/o a trace of any "adhesive". For that reason and the fact that inkjet prints are not waterproof, any such decal on tractors or equipment must be clearcoated. I recommend a test case to make sure of not only the correct printing orientation and scaling but also to verify that whatever clearcoat you use will not damage the decal material or the image itself. A urethane clear would probably be the best choice provided there was compatibility with your color coat. Be aware that clears are best applied within a limited time period after the color for the best adhesion properties.

That's if you want to do it yourself with commonly available equipment. I think there are some vendors that will (for $$$) take your photo or artwork and make professional cut vinyl or regular mylar decals of it for you.

Rod