It always amuses me how many opinions there are on this topic.
Simplest & cheapest is the 7806 chip - they're cheap, maybe $0.15 each. One for each gauge except your voltmeter. Put a 60 ohm resistor (precision wire wound) in series with it - it's close enough.
The runtz are resistors and aren't as stable as the digital CVRs. The 'factory' 56-9?? Ford item is a chopper and while it will work, also isn't stable. Like many things, there is more than one way to skin a cat and your opinion of what is 'better' is just that...an opinion. It boils down to what you value most...cost, simplicity, accuracy, ease of installation, or???