BMW 760 e65/e66 had separate electrics boxes just to drive direct injectors - those were the early days of GDI. Each v12 engine was running using two of these blocks - each box controls 6 lowZ injectors. Overall they had 5 separate control units to server that v12 engine.
We got one of these boxes - bosch 7506280 from BMW 760 - to click a GDI injector. Two wires to GND, two wires to +12v. Low-side control signal - and it's alive
Next step is hooking this to an oscilloscope.