Infinity^3 Times Baseline[]
Simon (Post-Multiverse Labyrinth)[]
Via this, the start of the scaling chain will start off with Simon the Digger being Infinity^3 x High 1-C. Simon integrated the multiverse, an infinite collection of 11-dimensional universes. This power is then amplified by his Spiral Power, to which he has an infinite amount of, which he sends flowing throughout Tengen Toppa Gurren Lagann. So… Infinity^3? Sounds about right… yeah it is right.
Simon himself is Infinity^3, because he awakened his Spiral Power, long before integrating the multiverse (before he fought against Lordgenome), so he doesn't need Gunmen to release his Spiral Power
Team Dai-Gurren (Post-Multiverse Labyrinth)[]
All of Team Dai-Gurren were given the same power as Simon. Each individual Dai-Gurren member (Post-Multiverse Labyrinth) are at this level
Tengen Toppa Gurren Lagann[]
Tengen Toppa Gurren Lagann was created by Simon and the others' souls, which means TTGL is also Infinity^3 x High 1-C. There isn't a likely 15 x Infinity^3 x High 1-C (via likely being created by all the pilots, which in the movie is 21 members), because there is a definitive moment in which all the members of Team Dai-Gurren become as powerful as Simon. Explained here, all members of Team Dai-Gurren became as powerful as Simon, AFTER the TTGL was formed. "There, a giant that crossed the galaxy was born. Tengen Toppa Gurren Lagann. The ultimate evolution of Gurren Lagann, created by swallowing all of our thoughts, wishes, regrets, hopes, past, and future. That giant, engulfed in green flames, was the greatest weapon that humanity, or rather the Spiral tribe, had ever gained. The face is on the chest, abdomen, arms, thighs, legs, and key points of the deformed body. It corresponded to each Lagann that Team Dai-Gurren was riding. Now each of them had the same power as Simon. However, Antispiral's voice echoed..." Therefore, it's wrong to say they were as powerful as him, before the Gunmen was created, because it was explicitly stated to happen some other moment. So... byeah.
Antispiral (Granzeboma)[]
Despite common misconception, even by me, Antispiral never suppressed himself throughout his in-person battle against Team Dai-Gurren. In the first minutes of this battle, Team Dai-Gurren had a difficult time against Antispiral because of the obvious power difference between them both. This is just to solidify the fact that Antispiral never held back this entire fight, so that other characters can scale to him at the end.
Team Dai-Gurren (Simon, Nia, Viral, Yoko, Boota and Lordgenome) [Post-Multiverse Labyrinth] are at this level
2 Times Infinity^3 Times Baseline[]
With this, we'll start with Lordgenome. He sacrifices his life to convert the Infinity Big Bang Storm into Energy the Team can use to become far more powerful. We can't use Antispiral's full scale for this attack as it would lead to many problems in the scale. The Infinity Big Bang Storm was going to quantum decompose Team Dai-Gurren if it were to go any longer, so at least Infinity^3 x High 1-C would be the reasonable level to put it at for the sake of the scaling chain. Back to the main topic, this is really easy to explain. Lordgenome is already 1 times, and he takes another attack which is also 1 times. It's safe to assume that him converting this energy attack into his own energy, to give to Team Dai-Gurren, would give him a 2 times multiplier in Attack Potency. 2 x Infinity^3 x High 1-C
Lordgenome (Post-Infinity Big Bang Storm) is at this level
3 Times Infinity^3 Times Baseline[]
Team Dai-Gurren (Epilogue)[]
Lordgenome gives all of his Spiral Power to Team Dai-Gurren, which therefore adds all of the former's power to the latter's. Team Dai-Gurren has now become 3 x Infinity^3 x High 1-C. This results in them finally being able to match Antispiral, as they break each other's drills in a drill battle.
Viral (Epilogue) & Boota (Epilogue)[]
Viral as one of the pilots of Gurren Lagann, and now having Spiral Power, he inherits the energy that runs throughout Gurren Lagann. Same as Boota. This can be assumed as this was the same process of inheriting Simon's power via being a pilot of Tengen Gurren.
Simon (Epilogue), Nia Teppelin (Epilogue) & Antispiral[]
Simon and Nia together, with Lagann, finally pierce through Antispiral's body.
Summary[]
Simon the Digger (Post-Multiverse Labyrinth) and Team Dai-Gurren (Post-Multiverse Labyrinth) = Infinity^3 x High 1-C
Lordgenome (Post-Infinity Big Bang Storm) = 2 x Infinity^3 x High 1-C
Team Dai-Gurren (Epilogue), Viral (Epilogue), Boota (Epilogue), Simon the Digger (Epilogue), Nia Teppelin (Epilogue) & Antispiral = 3 x Infinity^3 x High 1-C