Hy
I saw, this is an old theme, but, maybe can help. I am in "electronics world" about 15 years, now, I'm reparing the notebooks and LCD monitors but I'm living in country where is so dificult to buy any new part (inverter, motherboard...).
When we talk about inverter for notebook, I found that inverter have just 4 pins (not know what's the case in Mac Books), with only different arrangement for different laptops, but the same driving voltages, so you can put them correct after you identify them. These are:
0V-GND
5-12V Power supply (12V for LCD monitor, 5V for laptop)
0V(on) or 5V(off) backlight
and 0 up to 3.3V analog voltage for backlight stepping (IC on inverter is converting this into PWM, to regulate backlight intensity)
Just don't connect GND to wrong pin, you can damage the inverter board or fuse(maybe).
There is no special back signal from inverter, motherboard just have "intelegent" supply for inverter.
Frequently appearing problem in damaged inverters is high voltage transformer, his output coil burned. You also can replace him, solder the another one from same diagonal LCD screen inverter (they have the same transformers, same output voltage for ccfl). Longer ccfl works on higher voltage, so if you resolder the transformer from 17" to 15.4" (for example), ccfl lamp can die on highest intensity of brightness.
I fixed several notebook damaged inverters, replacing an incompatible inverter with modified arrangement of input wires. Some input conectors have (for example) 10 pins, but 4xGND, 4x5V, on/off and dimming siganl, but it's the same, just 4 different.
If you have any question, contact me or post the problem, maybe I can help
Sorry for language mistakes.
Good luck!