I made some pretty good ones. Than ran into a problem, apparently Lexmark re-formulated the ink, and the new ink ran and smeared,
ruining the artwork. I'd suggest an other than inkjet printing method. Mabey a Kinko's type place could run your artwork, and decal paper
through a high resolution lazer, or phaser type printer. Hobby Shops sell a Decal Fixitive, used on store bought decals. Testor's product
[ intended for model airplanes ] dries to a satiny finish . Could be gloss topcoated after curing. Hope this helps, the idea of printing custom decals is just too cool .