KC seems to be the only 70 Chevelle plant that used the broadcast code of CH, I found it on L34 Chevelles w/AC on 12-01 and 12-02 dated sheets. Sheets from at least 12-15 on shows CG in the fan clutch block. Might also have been used on LS5 and L48 w/AC at KC early on but don't have any sheets to confirm it but other plants used CG on L34, L48, and LS5 cars with AC.
Just to add a little to the debate, I have a build sheet from Van Nuys for a L34 with a M-20 4 spd and C-60 A/C with a schedule date of 11-12-69 that has the CH code. Only one I have. I also have a suspicion that the CH code may have been used in other years, most notably 1969. Anybody else have any confirmation? Also, most of these small 6" fan clutches in 69 and 70 have a part number and a date code on the rear of the mounting flange (part that would be against the pulley). This will give a definitive answer if it came from your car, as the date would have to preceed assembly of the vehicle.
Diamond Restored Judge
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