Regarding the EHX 1970s V1 series of treadle pedals (Crying tone, Queen Triggered Wah, etc).

These pedals were painted black, but for labeling the inputs and pots, they used this very unusual method. The labels are silver text on a black background on strips of some type of pliable metal (aluminum?) glued to the chassis. Does anyone know how they did this? It’s like an aluminum tape label maker or something. I cannot figure it out or find any info.

I have a pedal I’m trying to restore, and I can pretty much find a replacement for every part, but the labels are a mystery. If any one has any insight; I don’t know if anything has been posted online on the methodology.