Mopar enclosed trailer decals.

In my opinion... If you create the artwork, even if it looks like something copyrighted you should be ok.

no need to tell the sign shop what the M represents.

You could also have the seperate parts of the M made by seperate shops.

You could have a negitave made and paint it on yourself.

You could get a old style projector, project the images on the panel and trace it out and paint.