I bought a copy of the JPNZ manual direct for about $250 delivered to my door from memory. A 20% markup by AB any you get the $299...business I guess!
The manual contains enough information to see you through an an engine rebuild on any RB25/26 series engine. In addition it has all the ECU wiring diagrams and test procedures. However, some issues do exists. Yes there are spelling errors and some ommisions. On the preface, they say they edited it for suitability to Australia/NZ. I would have preffered a direct copy and allowing the buyer the opportunity to decide what is and isn't relevant. It also seems to be a bit haphazard in its organisation. There does not seem to be any reference to later series electrics, such as the integrated coil ignitors, and the inclusion of the throttle switch on some cars in addition to the TPS. And there are errors in some specs which you can correct by comparison to other sections. Unfortunately, there is absolutely NOTHING on anything else to do with the car....NO gearbox/diff/chassis/body info...which left me wanting.
If you have nothing then yes you do need this manual. But dont expect it to do everything for you. While $250 does seem a lot, there are probably 400 pages or so in there, and it would have been quite a bit of work to translate.