Marty Dusevich and his crew went to the beach (colloquially known as Shipwreck Bay) recently, fitting a stainless steel sleeve and returning the shaft to its original position.
They even checked photographs to be sure they had it facing the right way.
"Putting it up was the easy part," Mr Dusevich said.
Manufacturing the steel sleeve had been the bigger job, although the restoration had only been possible because a resident had taken the shaft for safe keeping when it collapsed more than a year ago.
Mr Dusevich said the nuts holding the sleeve had been welded so they could never be undone, and he hoped it would still be there in a 100 years time.
The actions of Mr Porter, who claimed to be protesting against the prospect of oil drilling off the Far North's west coast, were praised by some but roundly condemned by most.
He remained unrepentant, however, saying he had learned of the landmark's disappearance via social media, and that his action had at least prompted a robust discussion about the danger that offshore drilling represented to the environment.
Mr Porter had earlier said he had long disliked the name Shipwreck Bay being applied to the world-class surfing beach, saying that Te Kohanga (the nursery) more accurately reflected the nature of the area.
It was reported at the time that no one was seen taking what would have likely been a very heavy piece of rusted metal away as a memento, although that theory had not been entirely discounted. It now transpires that it was in safe keeping all the time.