Going to an incorrect offset may affect steering kickback, tramlining & RWS characteristics. It's the centreline of the wheel to the kingpin that's important, not the sidewall/arch position.
The NSX requires quite heavily backset spokes to clear the calipers too.
In other words, OEM's a lot easier.
Nick
“I find myself irresistibly attracted to cars that nobody else buys. The NSX is a classic of the genre because nobody buys it and yet it’s a fantastic car. It’s got a wonderful compactness and simplicity and unpretentiousness to it. Honda rudely continues to make them whether we like it or not, even though there can be no commercial logic in doing so — I thoroughly admire that.” Rowan Atkinson