American Motors: Disk Brake Changeover, quality grease, spindle nut

Question
I have a 74 gremlin with drum brakes and want to change over to disc brakes.  I got a disc brake setup from a 78 Concord.  When I cleaned off the old grease from one of the spindles from the Concord, I noticed that a small area of the metal was blueish in color.  Does this mean that at one time the wheel bearing went dry and overheated and now the metal has lost it's temper.  The junkyard says no that they see this from time to time and that there is nothing wrong with using this part.  There are no gouges in the spindle.  What is your opinion?  Thanks in advance.  

Answer
If the blueish color is located on the spindle directly where the inner or out wheel bearing is located, it might have been overheated. It probably won't hurt, especially if it's just a small area. Spindles are machined pretty thick and hard. It would take a lot to overheat it to the point of being dangerous. In those cases, the bearing will usually be melted to the spindle. I have seen blueish areas, but never had one break. At least under normal conditions. Take a new bearing and slide it over the spindle and make sure that it is snug. Be sure to use plenty of high quality grease when installing new wheel bearings and properly adjust the spindle nut.
Kevin