I researched this some. My parts history book shows the 3772532 wire clamp was to be substituted with 3704912 starting November 1969. The October 1, 1967 P&A 34 shows 1964-1968 all (8 cyl) clamp unit 3772532. The October 1, 1970 P&A shows 67-70 3704912 for all 8 cyl.
Steve