Just had a look at the 'Rail Industry Award 2010' and I would suggest based on an Operational Level 6 Driver of an 8,000Tonne they are on $835.70 per Week. + Allowances.
http://www.airc.gov.au/awardmod/awards/rail.pdf
So about the same as an FO on a regional when you add all the allowances. an extra $100k would put a driver on par with a Captain of Narrow body.