Just thought I'd share, because I have only ever seen 1 reference to this before, outside of Mark Stylings, and Stylings has gotten things wrong before, several times.
I believe it's from Squadron Signal:
Pretty good work Greebo! It's possible the font on the "96" was more misshappen because it was hand painted, but that's a minor point. I'm more curious about the demarcation under the fuselage... Almost looks like 2-tone paint, but might be just the weathering of a 1-tone paintjob (more likely). Funny effect, though!