David Parker will get Cunliffe's present finance spokesmanship - a position he has long coveted - as the quid pro quo for withdrawing from the election race and assuring Shearer's win.
This week's deal was essentially put together by long-serving MP Trevor Mallard - who performed the numbers role when Helen Clark ran her coup against then leader Mike Moore.
But much of the real strategising started several months back when Shearer and close caucus allies such as former Labour list MP Stuart Nash seriously began talking about a post-election leadership tilt.
Influential members of the "commentariat" - particularly those of the right-of-centre persuasion - were informally briefed.
Shearer was promoted as having a modern international outlook; pro-business, pro-science and innovation, and not prone to the phony cloth-cap ideology that Goff had to dip into to retain the confidence of the Labour unionists who have for too long dominated the party.
In other words, the right politician to drag Labour into the 21st century and out of its ideological cul-de-sac.
But it was Conor Roberts - who is currently acting as "Len Brown's brain" and ran Shearer's Mt Albert campaign - who came up the killer meme: "John Key went overseas to make $50 million; David Shearer went overseas to save 50 million lives".
It was no coincidence that right-wing commentators were among the first to start spouting this rather over-drawn claim once Shearer's candidacy was declared. It had after all been a point of conversation at a post-election party the previous day attended by well-known commentators from left and right persuasion, a smattering of bloggers and Shearer. Cunliffe - who was also invited - did not show up.
This is the reality which belies the "Anyone but Cunliffe" faction's convenient claim that Phil Goff was seriously undermined by just one person, his finance spokesman.
Let's face it, the total lack of confidence in Goff's leadership has been writ large since senior MPs were photographed standing behind him after a special meeting to reaffirm support for him after his disastrous handling of the Darren Hughes affair.
The party did not even bother to put Goff's face up on its billboards. This was a very public vote of no confidence.
Today Shearer, Robertson and other allies will be determining the final caucus lineup. They face a problem in that Parker does not have Cunliffe's killer instincts. He is not as respected in the business community. Parker is also in love with a new partner; a condition which does not easily lend itself to "putting on a hard hat" and venomously taking it to National on a daily basis.
Former leading Maori businessman Shane Jones recognises this.
That's why he has urged Shearer to adopt David Lange's approach and pole vault some hard-headed MPs (naturally himself foremost) on to the front-bench as his parliamentary attack dogs, leaving the leader free to build a broader constituency outside Parliament.
Jones has rat-like cunning. He is a potential challenger to Shearer if the political neophyte fails to change the perception of the party.
He will also regain the opportunity to shine in the debating chamber in front of other MPs - something which Shearer, who until now has been a mere backbencher, has yet to demonstrate.
But Jones also has a serious point.
When Lange rolled Bill Rowling he catapulted the infamous "fish and chip plotters" Sir Roger Douglas, Richard Prebble and Mike Moore to very senior roles, Lange reaffirmed his desire to be surrounded by politicians who were "surging in debate" and "active in the cause".
But Nash will have urged Shearer not to offer Cunliffe a high ranking on the front-bench.
It appears he still nurses a sore point that Labour's finance spokesman did not give him sufficient credit for the work he did as revenue spokesman on the party's election tax package.
Nash has made no secret of the fact that he would prefer that Cunliffe exits politics altogether.
It would appear that Shearer is looking to elevate Jacinda Ardern, Jones and Clayton Cosgrove as his attack dogs.
If, as expected, Shearer does appoint Nash as his chief of staff - bridges will have to be built if Cunliffe does decide to swallow a very dead rat, take a demotion and stay on in politics.
Cunliffe being Cunliffe will be feeling deeply insulted by being offered a role he would feel so insultingly beneath his proven capabilities.
But he was also one of the few stellar performers in Goff's team.
If Shearer is not captive to his supporters he will put some undeserving long-servers to the sword first.