I've finished up the remaining survey required for Campbell's Pocket Road Queensland, (I had missed a bit of the road last time, and that has a couple of other minor roads running off it as it turns out).
On the way out there, whilst in Dayboro getting pies from the bakery (!), I noticed a commemorative permanent survey mark on the site of the old railway station - placed there as part of the Q150 celebrations last year - here's a couple of pictures of this Dayboro Survey mark:
S27 11' 44.96"
E152 49' 31.40"
The plaque mentions this website http://sssi.org.au/q150 - and that site has a PDF of all the survey marks placed in Queensland, along with the tagline "Everywhere for Everyone"... the dataset is copyright though and unsuitable for import into OSM :-(
The one I found could be added though - but how to tag it?