During our CANbus R&D testing we have figured out a way to control the charging voltage on systems using a E38 ECU and no BCM.
We have incorporated this into our Jeep JK LS Swaps and it has been working great. We are thinking about releasing it for the guys running LS swaps in other vehicles.
We are basically starting this thread to gauge interest and to get feedback for options that would make it more appealing.
The module would be about the size of a relay and could be hard wired (4 wires) or simply plunged into the OBD2 port.
The basic controls would be maintaining a set voltage, lets say 14.4
other options could be RPM based. At low rpm's drop the output to help lower the load at idle, or at high rpm's WOT lower the voltage to lower the drag on the system.
If you have other needs or wants feel free to chime in.