The Marree Man will never be re-instated, for the simple reasons that even the smallest amount of environmental damage to flora in semi-desert country is no longer tolerated, nor acceptable. For the same reason the Readymix logo on the Nullarbor will never be re-instated.
For many decades, utilising tracked machines in exploration or mining-lease gridding work has been banned in South Australia, due to the express reason that it is deemed too damaging to the environment. Only wheeled machines are allowed to be used, and even their use is heavily monitored and restricted.
As an agricultural and mining earthmoving contractor in a previous life, I can assure you the mid-1980's saw a massive "green" revolt over excessive agricultural land-clearing, excessive mining and exploration flora damage, and uncontrolled works involving any destruction of native flora.
Extensive salt encroachment on cleared farmland in W.A., plus the realisation that extensive varieties of both native flora and native fauna were being wiped out at an alarming rate - with many species possibly not even being recorded before they were made extinct, led to the upswelling of the "Green" grassroots and political movement, which now has entrenched political power and a highly vocal front.
This movement is stridently vociferous whenever it sees a blade of grass being damaged. The continuing clearing of native vegetation for farmland in QLD is their major target at present. I fully expect them to chain themselves to the bulldozers shortly.
Somewhere along the way, there is a balance between unnecessary and excessive clearing, and the stopping of any form of development.
However, the creation of the Marree Man was highly illegal in the first place, and any attempt to recreate it, will be met with strident Green opposition, and legislative punishment as well.
The equipment needed to create it would not have needed to be anything more than a moderate-size bulldozer, preferably fitted with an angling blade - or even just a motor grader, if the operator was skilled enough.