I though some folk here might be interested in a website I've just published, called https://historicalmaps.online
It has a number of old maps of the Snowy Mountains which I've geo-referenced. The old maps sit on top of a current day map. You can zoom into points of interest, and by clicking on that POI, you can copy the Latitude and Longtitude into other mapping tools.
Also created a demo on how to use the site that will help getting started
https://youtu.be/BWHv2Ey1MbY
I'd love to add the Budawang Sketch Maps to the collection, but they are currently in copyright. If anyone knows the Elliott family and think they would be OK with me displaying the map, please PM me.
I hope to add more maps in the future, so open to suggestions, but they need to be of interest to bushwalkers and be out of copyright.