741 Ring and Pinion Bearings

I only have one of my books here at the moment but it's showing the '68 and older carriers using the 25520/90 bearings and the '69 and new ones using the 2852728/9'S which is probably the Timken LM numbers you listed. As for the actual specs difference....I'm not sure....I'd have to put some calipers on each of them. If nobody knows before I get a chance, I'll see if I have a set of each and measure them.