Rear uprights (disc brakes)

[DRCorsa Engineering]

Hello everybody.
Next week i am gonna make my uprights, i am running disc brakes at the rear.
I have read somewhere that plate RU7 and RU8 should not be welded vertically -as the book states- but at 45deg angle to the vertical. Is this true?
If yes, could someone please post some pictures of the configuration? The upper edge of the RU8 plate should be towards the front or the rear?
Some pictures would really help here. Thanks a lot for your help!