Range/Dryer Power Cords

It's a long story, but I found occasion to need to change the power cord from a 3-prong plug (NEMA 10) to a 4-prong plug (NEMA 14).  There's a useful howto online that clearly describes the process.  Following these instructions, the switchout went off without a hitch.  The GE-made 40A cord cost $20 + tax at Home Depot, though!