I DO have late aluminum arms. Mine are exactly like the ones Zen is using on his '73, and should be like yours too. The rotors that came with those arms are too large for the N/A calipers.
What rotors are you using on yours? Do you have a part # handy?
__________________
Yetibone
'71 1302S 1.8
'73 1303S 2.3
'83 928S 4.7
|