2.42:1 OR 2.41:1 Lower Unit Identification

Hello Everyone,
So I recently purchased a 2002 25HP Four Stroke for my brother in law. According to the cowl it's a bigfoot model, but I'm having issues getting a definitive answer if this is true or not. The serial number is 0T490837. According to the mercury website EzPartsWeb it shows it's a 2.41:1 but on the lower unit itself it has the sticker showing it's a 2.42:1. From my understanding with the bigfoot models you gotta know your part number specifically for the impeller kit.
I'm gonna go through the entire motor this winter for him but want to be sure I know what part numbers to look for.
Any help?

How about pic of lower unit and prop hub diameter

Well----I think 2.42:1 and 2.41:1 is the same thing in this application.----So 12 teeth on pinion and 29 teeth on gears would give a ratio of 2.41666 or so.------Could be written as 2.41 or 2.42 if rounded up.----