How to Tell the Difference Between LY7 and LLT
 

Hello,

I was given an engine out of a 09 CTS that was in a car that was being destroyed in the movie industry. It is a 3.6L V6 but it looks like in 09 you had the option between the LY7 and the LLT. I do not have the vin nor can i find a LY7 or LLT stamp on the engine block. Without the vin how can you tell which engine it is?

Thanks
Michael