A bushy tailed 18yo me on the "Scarifier".
This would be a few k's in front of that other machinery ... 1st the Extractor which would pull-chop out the failed wood sleepers & then the Scarifier would simply clean up for the new sleeper to go in..... Mean while the Concrete sleeper gangs were starting to come across from Pt Augusta.
Think the Extractor was made by Comeng & the Scarifier by Fairmont.