I would like to do this too but my lettering is messed up at the bottom.
Honestly, I am strongly considering making a plastic mod like I did my airball mods. Let me know what you all think of this (i'm not sure it can be done but you never know). Might not be worth the hassle.
Imagine a plastic mod shaped just like the decal, color matched as close as possible, lettering printed on. It would be slightly thinner than a credit card and rigid. Adhesive on the backside. I would shave both ends for a smooth transition. You could simply adhere and be done, no body filler, jb weld, sanding etc.
I got the idea because I am using a credit card until I get this patched. The bondo I used must have reacted with the heat from the magnet and it caused it to lift under the decal. I had to remove it all after I applied the decal in the image above. The sanctum wasn't working again as the ball just fell down. The surface must be perfectly smooth as you know. So I am back to square one. I planned on replacing the sticker because it stuck out like a sore thumb. The individual who sold it to me on ebay is very cooperative and making a few darker versions for me to see which one matches best and he can then sell a more accurate product. The credit card works fine but the edge does cause the ball to jump and hit the plastic above.
Imagine a product in which you never had to patch, just apply and be done. Think it would sell?