Is it just Me?
It coulda been a typo since it's only one number off, but ya never know. Your correct, if they write they should know what's what but I've caught several mistakes in magazines.
A few months ago Car Craft did an article on Mopar 8-3/4 rearends. It was written by Steve Mangente (sp?). If you don't know that name he's one of the guys that announces on the Barrett Jackson auctions. He had several mistakes. He showed a picture of a cone type sure grip calling it a rebuildable clutch type and said all sure grips directly interchange, bearings and all. The sure grips will interchange but the bearings are specific to each sure grip. Had a couple other mistakes that I forget at the moment. I posted a response on their website politely correcting his mistakes but got no reply and haven't seen it printed and it's been 3-4 months now.