1969 C body shock lengths and info :

monroe #32073 - rear - 13.750 compressed, 22.875 extended
mounting : LS39 top - 1/2"id. sleeve, 1 5/8"wide
L2 bottom - 11/16"id. bushing 1 9/16" wide


monroe #LE10009 [sold as pair] - front - 8.000 compressed, 12.250 ext.
mounting : S top - straight stem - no dust shield
LS15 bottom - 7/16"id. bushing, 1 3/8" wide

hope this helps. info from my monroe master catalog.