Here are some topics from here where this was discussed. Sorry I don't know how to make a link here but I think you can copy and paste it into the search box.
rod length question for 292's, Forged pistons from LS1 in 292, Re: Piston & Rod Specs?.
As you ca see this is not a settled issue. As you did not tell us which engine from the specs I assume it is a 292.
