I don't think it's really an issue. Folks like me are just curious sorts. I only mentioned the older horizontal type engines due to their popularity and that they are 2-cylinder jobs. They aren't related in any other way to the LU series of engines other than being manufactured by John Deere.
A fellow I used to work for had one of those old 1908 Brush Runabouts. It only had 1 cylinder with a wood frame & axles and it would go about as fast as a tractor but it was still a lot of fun.
Your JD is undoubtedly a lot of fun as well.
I've seen photos of a 3-wheeler cycle that had the JD green LUC on the back.
https://www.flickr.com/photos/32719051@N06/3790954346