BMS for separate Chevy Volt Module

[lettersize]

I planning to rewire Cherry Volt 48v 45ah module into 24v 90ah.
Module consists of 12 cell groups (each cell group have 3 LG Chem LiCoO2 pouch cells.), so by connecting cells groups 2p 6s i should get 24v 90ah module.

What kind of BMS will i need for this?
The set-up i use has continuous current is 30A. peak current is 60A.
I guess BMS must ensure "Golden Rule of LiPo":

***Golden Rule of LiPo*** If you break this rule, you are pulling the pin on the grenade.
Absolutely NEVER Exceed 4.3v/cell, never Discharge below 2.7v/cell, never puncture the cells.

So basically BMS must cut of charge if cells reaching 4.3v/cell, and cut of discharge if cells reaching 2.7v/cell.
The cells are in cells groups(3 cells wired in parallel). So i won't be able to reach individual cells - so do i just connect BMS to cell groups,
and it must and cut of charge if cell group reaching 4.3v/cell, and cut of discharge if cell group reaching 2.7v/cell. Am i getting this right?
p.s. attached pictured are taking from here.

 

[Harold in CR]

If you are not ABSOLUTELY certain of the module construction, DO NOT cut through the wide flat part of the cell connectors.

The balance leads run directly under that connection and SERIOUS Amps will be encountered if you cut/Short out those balance leads.

 

[Warren]

Reading through this Volt pack disassembly, using a bandsaw, cut-off wheel, and mill, might be helpful.

http://www.schultzengineering.us/delta-11-12.htm