This is off the top of my head, so y'all chime in and correct/add where appropriate:
I think the first calipers came out in about 1969 and had no script. In about 1971 the block lettering began. Early bolts were engraved with the Brev. vs. Patent. Early quick releases were flat. This continued to about 1978 when the domed QR's came out. I think this is when the Patent stamp replaced the Brev. stamp on pivot bolts. Early brake shoes were chromed steel with no plastic on the guides. In about 1978 or so, the chromed steel continued for Nuovo Record brake calipers, but now with plastic coated guides. At this time, Super Record calipers were differntiated and used alloy brake shoe holders with plastic coated guides instead of the chromed steel used on Nuovo Record. In approximately 1984, subsequent to the introduction of the 50th group in 1983, the script lettered thicker-profile style calipers came into general use. These used a different domed nut on the pivot bolt and also used an allen head rather than 8mm hex for the cable pinch bolt. I think first year of the Cobaltos was '85??
Jeff Pyzyk
Milwaukee, WI