Timken boat trailer bearings question

[5keepers2]

My trailer takes the standard 1 3/8 x 1 1/16 tapered bearings. L68149 and L44649.
My local Timken dealer ask me a new to me question today. Do you want small or large cups or races for those bearings?
I replied I don't know. I bought several bearing sets over the years and never was ask that question before. I was told the large cup or race is 1 mm larger. Other than 1 mm larger they are identical.
I am buying these bearings as spares. My trailer hubs are on trailer and running fine and I can't measure. So I guess I buy small......what ya think? Comments and your knowledge here appreciated. Who knew there were 2 sizes not me?

[fastfiat]

Just measured one I replaced last month. Outer bearing race is 1.978 and the inner is 2.360. Takes the bearings you listed and are on my 97 Champ trailer. I know the inner are the larger of the two races. The small inner race measures 2.330 and is loose in the hub. For piece of mind you can order races separate from the bearings if you're not sure.

[Mechanic Bob]

Until you remove races and look at the numbers it is hard to tell. When I rebuilt my hubs, I ordered the larger races, and they did not fit. Ended us using the existing races, had no choice and they were not damaged, so it worked out well.
But I would order both sizes if doing it again.

[61Woody]

Until you remove races and look at the numbers it is hard to tell. When I rebuilt my hubs, I ordered the larger races, and they did not fit. Ended us using the existing races, had no choice and they were not damaged, so it worked out well.
But I would order both sizes if doing it again.

Same here a few weeks ago, numbers were the same but neither of the new ones would fit. Ended up using new bearings and old races.