Where to find pinout information for the E40 ECU

I have an E40 ECU from a 2006 Chevrolet Impala SS. I would like to use this on a 5.3 Vortec engine I plan to modify and transplant into a Jeep. It seems the E40 is kind of a red headed step child in the GM family of computers and finding the pin configuration is proving to be difficult.

I am not sure where to look to find this information at this point. Is it available on the web for free anywhere or can I at least buy it somewhere if it isn't available for free? Anyone have any advise?