From the Pozzi racing site.
http://www.pozziracing.com/camaro_st...part%20numbers
PITMAN ARMS
MANUAL LONG 5.8", 3953225 (5671822 this number was given to me but not sure of it, does not start with 39xxxxx)
GM part number (casting number)
MANUAL SHORT 5.25", 3953217 (on part 3953219)
POWER LONG 5.8", 3953237 (3953227 on part late, - 3908391 1967 early-thinner)
POWER SHORT 5.25", 3935711-late -3935075 3953231-327 eng -early?