I spent the better half of Monday completing SVG files based on the 1961 California U.S. Highway shield and photographs of the technicolor signs Arizona used in the 1950s.
(https://upload.wikimedia.org/wikipedia/commons/thumb/7/75/US_91_Arizona_1958_North.svg/200px-US_91_Arizona_1958_North.svg.png)(https://upload.wikimedia.org/wikipedia/commons/thumb/3/3f/US_93_Arizona_1958_South.svg/200px-US_93_Arizona_1958_South.svg.png)
(https://upload.wikimedia.org/wikipedia/commons/thumb/5/5f/US_80_Arizona_1958_East.svg/200px-US_80_Arizona_1958_East.svg.png)(https://upload.wikimedia.org/wikipedia/commons/thumb/d/d8/US_70_Arizona_1958_West.svg/200px-US_70_Arizona_1958_West.svg.png)
And here's a 3DX version created using the only Highway Gothic font that would fit the parameters. I can't confirm the accuracy of it as I could not find any photos of a technicolor sign being used on a 3DX such as US 260 or US 666.
(https://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/US_260_Arizona_1958_West.svg/240px-US_260_Arizona_1958_West.svg.png)
For those who haven't seen these before and aren't familiar with the signs, each color is direction specific.
Orange = North
Green = South
Blue = West
Brown = East
The colors of the shields are the MUTCD approved ones as that is what they appeared to be when looking at the few extant photographs of these signs. I found out sadly enough that ADOT tends to destroy unneeded highway shields once they are taken down, meaning these technicolor signs would likely be a rarity today.
What's old is new again – sort of. Check out these green shields which just went up on a newly completed 4-lane section of US 93 between Wickenburg and Wikieup. There are only a handful of them; the segment wasn't very long.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi907.photobucket.com%2Falbums%2Fac274%2Fmartinbartlett%2FIMG_2405_zpsz1zpleym.jpg&hash=eecdf53f0237d4d6db17d22156a106173a788c6a) (http://s907.photobucket.com/user/martinbartlett/media/IMG_2405_zpsz1zpleym.jpg.html)