Obviously do as you please. For precisely the reasons listed in that snippet, it would make me uneasy. As long as your original cups are there (I'm assuming it's an adjustable bb), it's easy to repack it and replace the bearings or spindle if necessary.

Regardless, to avoid confusion, it's important to note the OP asked about an early 70's Peugeot. Peugeots were French threaded through the late 70s. In addition to the difference in thread pitch, French and ISO bb shells don't even have the same thread direction -- swapping the spindle is the only time/cost-effective solution.