My 67 has a 12 bolt that is 70-72 vintage I believe.. 3969278NF plus the number CCF1117B1.. Can anyone give me any other info on this... Thanks,

CCF1117B = 3:31 posi, built Nov.11 at Buffalo facility ...... I think in 1969 for '70 model year.

My 67 has a 12 bolt that is 70-72 vintage I believe.. 3969278NF plus the number CCF1117B1.. Can anyone give me any other info on this... Thanks,
You are correct that the 3969278NF casting number identifies it as a 70 to 72. Assembly code format narrows it to 1970 model year only. CCF = 3.31 posi and 1117 = November 17 assembly date (1969). B = Buffalo assembly plant and the 1 indicates first shift.
Bruce

Jim beat me to it.:thumbsup:

Rear end will work fine under your 67. It's a bit wider than the original and that will affect your tire/wheel selection somewhat. Wheels need about 1/2" more positive offset to gain more backspacing than normal. Running 14"-16" with a deeper offset may interfere with things like shock mounts but a 17" or larger wheel should clear them.

Thanks for the info! I read about the rear-end being a bit wider and don't really know what size wheels I want to go with... I'm a long ways from that point of the project but when I get there I'll be askin' questions.. Not really clear on the offset issue.. Thanks again...Don

I have it explained on my web site - http://www.chevellestuff.com/tech/wheel_offset.htm

* 1964-67 Chevelle rear ends were manufactured by the Chevrolet Gear and Axle Division. The housing measures 53.25 inches from backing plate to backing plate and with the brake drums in place, the total width is 60.00 inches.

* 1968-72 Chevelle rear end housings measure 58.5 inches from flange to flange, and with the brake drums in place, the total width is 62.5 inches. (Note: Other sources put the total width at 61.125" to 61.25".)