Inliners International Forums General Discussion Engines Casting Number Confusion!

I have a Chevy Inline 6 with casting # 3788378. All of the charts I looked at say that this is a 292. It definitely is not. The side covers are 4", the motor mounts are not staggered, and the fuel pump location is wrong as well. Are all of the charts wrong or was this motor stamped incorrectly?

Thanks!