Town had lost 7-0 at Blundell Park back in October, but avenged that horrendous night with a stunning victory that seemed inspired in part by consigning that hammering to history - what a difference four months makes.
Three goals in 20 first-half minutes from Billy Whitehouse, James Bolton and Nicky Wroe put Town in control before Jake Hibbs added the late gloss to hand Halifax a huge boost to their survival hopes.
It hardly mattered that Jon Nolan and Padraig Amond scored for Grimsby.
In front of the biggest Shay crowd of the season, Halifax were everything they weren’t during the reverse game with The Mariners - organised, disciplined, committed and a potent threat on the break.
Only Plymouth and Wycombe had conceded fewer league goals away from home in the top-five divisions than Grimsby before the game, but Halifax made a mockery of that statistic as they swept aside a team with 13 wins in their last 19 games.
Jim Harvey admitted during the week he was concerned where the goals would come from following the departure of Shaun Tuton to Barnsley, with Town failing to score for the first time since his appointment against Forest Green and not scoring more than once in their last six matches.
He needn’t have worried.
The Town manager’s attempted solution was to drop top-scorer Jordan Burrow to the bench and hand a debut to Doncaster loanee Whitehouse, who started on the left of midfield in a 5-4-1; what a decision that turned out to be.
Kevin Roberts, one of five survivors from the 7-0 horror show at Blundell Park along with Kingsley James, Bolton, Matty Brown and Wroe, began in the centre of defence and looked like he’d played there for years.
The atmosphere was reminiscent of previous games where all four sides of The Shay were in use, such as Luton and Bradford, and even before the match, the 1,767 Grimsby fans were making quite a racket.
The visiting supporters in the North Stand outnumbered those opposite them in the South Stand, but the Grimsby fans were soon silenced when Bolton’s deflected cross fell perfectly to Whitehouse, who slammed the ball past James McKeown for his first senior goal in his first senior start since September 1.
But hell hath no fury like Grimsby scorned, and the away side came mightily close to equalising twice in the next five minutes, first when Josh Gowling’s shot was cleared off the line by Roberts.
Then the country’s second highest scorer Amond’s header was brilliantly saved by Sam Johnson from an angle.
It looked a matter of time before Grimsby levelled, but superb hold-up play by Richard Peniket led to the hosts winning a corner, from which Bolton put Halifax into dreamland with an unmarked header from the impressive Scott McManus’ fine delivery.
Wherever is nicer than dreamland, Halifax were there barely two minutes later as a rapid break saw James maraud down the left flank and expose a beleaguered Grimsby defence before finding Wroe unmarked, and the Town captain swept the ball into the unguarded net.
There were flashes of the way Grimsby tore Halifax apart on that awful night last year as the away side’s defence was pulled apart.
Grimsby were 4-0 up by half-time back in October; Halifax were one shy of doing the same as the home supporters chanted “we want seven”.
If Harvey was worried where the goals would come from before the game, he surely wasn’t now as Town struck three in a game for the first time since Tamowrth in December.
Amond and Omar Bogle had combined to devastating effect in the reverse fixture, but they, like the rest of the Mariners team, looked shell-shocked at their predicament, having conceded three goals in a game for the first time this season.
A double substitution at half-time showed what Paul Hurst thought of the first-half, but there was no fightback, with The Mariners continuing to look all at sea.
Town had Grimsby right where they wanted them, and were composed in their defending, limiting the visitors to few chances and offering a threat themselves on the counter-attack.
Grimsby offered nothing other than intermittent wayward long shots, while substitute Burrow nearly added a fourth when he shot low across goal from Shaquille McDonald’s lay-off.
Grimsby did get a goal back in the dying minutes, but even that was courtesy of a helping hand as Johnson’s poor punch at a corner fell to Amond, who bundled in.
Town thought they’d had the last word when substitute Hibbs curled in a sumptuous free-kick that his travelling partner Sam Walker would have been proud of.
But Grimsby again reduced the deficit when Jon Nolan’s drive whistled into the bottom left corner from the edge of the box.