Just fyi, the legends in the first photos posted are not decals - they are Dymo labels. 'Dymo' was a hand-held stamping machine that reverse-embossed a strip of coloured sticky plastic tape for home labelling purposes. It was very common for every use in the UK in the sixties, and was very often seen on racing car parts.
I'm just looking at my 40-yr-old Dymo machine now...
...seems like they're still about, but they've smartened up the design a bit:
https://www.ebay.co.uk/p/Dymo-S07179...d=192118138289
Roger
'course, it's more than likely that these are US items anyway...