Rory - I'm sorry if I seem rude! Re your enquiry on rms about Pommie Holdens - I only just saw it, and that was through Google Groups; there seems to be a lot of articles I'm missing out on by using my ISP's newsgroup thingy. The trouble is that I don't want to go through all the bother of having to create a Google a/c and then log on every time I want to look at rms; or I can just be rude and not answer enquiries.... a conundrum indeed!
As far as Pommie Holdens - the early Commodores were based on Opel/Vauxhall floorpans - until about the late '80s, if memory serves. The really early Holden Toranas were rebadged Vauxhall Vivas. Most of the rest of the Holden stuff is/was (mostly) local in design and construction, although a lot of Holden engines over the years were GM boat anchors from the Mother Ship. That said, the local chappies have designed some damn fine engines - the 6cyl 'Red' motor and the 253/308 cid V-8s come to mind. The new 2dr Commode (joke) is being exported to the States, I believe - do a search under Holden Monaro - you'll also get some pics of 'real' cars - muscle thingos from the late '70s, if you're lucky. Holden's Motor Body Co (I think?) were a small coachbuilder that got involved with Australia's first car and then got involved with GM at some point, hence the worldwide connections. Have a look at the Holden corporate website - it may have a bit of history there.
After all that, I think you may have asked the wrong guy - I'm more an Aussie Ford man. If there's any Aussie model building Holden fans here, don't be shy - pad up, grab the willow and let us know!
RobG (the Aussie one)