I contacted Richard from mx5plus.com.au and bought for a very resonable price, a custom replacement front number plate bracket for my NC and am very happy with the results...
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After

Before

After

$22 (plus $5.50 postage) and 5-10 minutes installation time. All you need is a battery drill, a phillps screw driver and a pop rivet gun...
I also forked out for some white on blac slimline plates for $144 from Vic Roads... got some for my Commodore as well. Of course, the normal Kingpin number plate cover from my local auto shop for about $30 a set (of two).
Here's the link for the part from mx5plus.com.au. http://www.mx5plus.com.au/part_display.php?part=28&cat=5