http://www.pozziracing.com/camaro_steering.htm Scroll down about half way and look at "Outer Steering Arms - Three Lengths!" see below
OUTER ARMS
Lengths are from center of spindle between attachment bolt holes, to center of tie rod hole.
Remember, Nova, Ventura, Omega, up through 1974 uses the same subframe as Camaro!
SHORT 5.25" LH-3954875 RH-3954876 Used on power steer, and Z/28 fast ratio manual.
SHORT LH-3902519 RH-3902520 turn stop pad is more pronounced on top, arm appears a bit thinner than later arms. 1968
SHORT LH-3954879 RH-3954880 (listed in parts book as 5.312" long, this may be the actual correct length for all short arms)
SHORT JL8 four wheel disc arms, 1969 Z/28 Heat Treated, Shot Peened, (probably short 5.3") LH 3916237, RH-3916238
MEDIUM ARM 5.5" length RH-3916266 LH -3916265? not sure what ratio. 67 and into 68 manual steer.
MEDIUM ARM 5.5" length RH 3954874 LH3954873 - All except for PS and 302 1969 only.
LONG 6" manual, - LH-3902517 RH-3902518 (67, early long measured at 6") LH-3917193 RH-3917194 slow ratio manual steering.