300ZX? no wonder you own a hoist!
Nik get some camber bolts for the front or grind the raised section off the original bolts at least so you can get the camber spot on. Although you say you are happy with your alignment from the figures they have not spent the time to make it perfect (not that hard trust me)
Nick in regards to the camber gauges i have used long acre and various other expensive items.
BUT what i like using with the car loaded on jack stands with wheels off is one of these builders angle gauges that Steve has. Use that across the centre hub and it is as accurate as it gets! and dirt cheap.
For toe i use Longacre toe plates and tape measures.