The hardware on the block logo and script logo calipers is mechanically interchangable but cosmetically different in several areas. These changes were made going from the block logo to the script logo:
center bolts (logo deleted) outer friction washer (the one behind the adjusting nut. Serrations were deleted) locknut (becomes conical w/ two flats) serrated washer (against frame... logo deleted) locknut for QR cam mech (becomes conical, w/ blind opening) cable anchor bolt and plate (goes from regular hex to countersunk allen head. also, can't use the old bolt with the new plate and visa versa) brakeshoe mounting nuts (become flatter)
There was a minor change to the alloy pad holder at some point, but I think it was before the block-to-script change.
FWIW, the levers were also changed at this time. The part that holds the cable end had teh logo deleted and the shield logo hoods were introduced (though others maintain that the shield hoods were earlier, I'm pretty sure that came out with the script calipers).
The bottom line is that there are a lot of differences other than the arms. I'd be willing to pay quite a bit more for a nice block logo brakeset compared to script.
Tom Dalton Bethlehem, PA
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