Need help with motor plate measurement and engine offset

[Lsguy]

Not sure if I'm posting this in the right spot. I'm needing help with motor plate measurements i bought the car as a roller so there was no Factory mounts to be able to take any measurements. I'm ordering a custom motor plate from AEI and need to know the crankshaft Centerline measured from between the frame rails. If someone could possibly measure from the inside of the frame rail to the center of the crank are if someone knows what the engine offset is I would greatly appreciate it. I was told the engine does not sit directly in the middle of the engine bay that it was all set to one side or the other