1965 Dartcharger

Finally it was time for this car. The rear axle is assembled and ready for rear axle cover. I found a NOS one in my stash and a new gasket is ready.
The axle has some markings. 02070051 must be the casting number on the house alone.
Triangle + 10 means?
Next is 821. My guess is that the center section was casted 821 meaning August 21st 1964.
The left side pipe has a stamped F. Not sure what the meaning is but might be the length of it.
After adding the cover I started wonder if the last screw with the clips holding the brake line should be unpainted? If it were mounted before the the paint was added the line workers needed to dis-assemble the bolt and clip and bend the clip over the brake line and then mount it. Any thoughts?
When everything was ready for paint the brake shield was not in place. They were black phosphated and mounted with the white foam gasket inside out after the axle housing were painted. But were the special bolts added on each side that holds the brake sheld before or after the housing were painted?
Since the axle was not filled with oil before the paint process my guess is that the plug were added after paint. The line workers put a red paint splot in the middle of the plug after filling the axle with oil and tightened it.

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