> What the good doctor is referring to, is the extra metal journal box left on the truck sideframe, that did not allow for proper roller bearing hotbox monitoring at trackside detectors. I didn't know this, but it make perfect sense.

What I'm referring to is converted boxes on all fomerly friction bearing trucks, not just the ones in the three axle ones. The 2"+ hole drilled below the lower lip of the box was for letting out dirt and mositure. The rest of the box left under the roller bearing itself is what prevented the HB detectors from seeing the RB's outer race to check for overheating.