Don't recall the piston part # off the top of my head but they are the 12:1 compression pistons for the de ( translates over to something close to 9:1 maybe a bit higher with the sohc head I am using. )
As for the aem this car actually uses a v1 sorry the pic I posted is indeed a v2 unit. Both the v1 and v2 utilize the stock harness although the v2 must use the aem cas disc (i would recommend using the aem cas in the v1 units as well though) I've done my fair share of bothe v1 and v2 aem ems's and strongly recommend them for any tuning needs
I know alot of people have questions about the aem ems, by almeans everyone feel free to hit me up with questions any time I am always happy to help out!