Missouri Pacific RS2s: Roller Bearing or Friction Trucks?

Did MP RS2s have Roller Bearing or Friction Trucks? I was looking @ Kato Undec. RS2s on sale @ BLWNscale and wanted to know which was correct. [sigh]

If you have a picture of the prototype’s trucks, it’s usually easy to tell. Friction bearing have the traditional journal box lid, and roller bearings have the bolted on cap.