MBP Bad Display? Goes black randomly.

I am having an issue with my Macbook Pro display which I have seen many variants of surfing the intertubes here. The screen goes black more or less at random. I am hoping to avoid having it serviced as my black tie service plan expired last november (bought this at Best Buy.) When the screen is black the computer is still running.

This has been happening intermittently for a while now, and in the past week has rendered my MBP effectively unusable.

Before making any suggestions, please read this list of commonly suggested ideas I've tried which did not solve the issue:

The power saver/display sleep is set to 1 hour, it is not coming on.

The screen saver is set to “never”.

I ran a software update a couple days ago.

Shutting the lid and waking the machine back up doesn’t matter.

F2 (increase screen brightness) doesn’t matter.

Dimming the screen (holding F1 for about 10 seconds) before increasing screen brightness also has no effect.

My external display WORKS, I can shut my lid and use my computer normally with external display, keyboard, and mouse. I believe this rules out the display board issue: http://support.apple.com/kb/TS2377

Holding a LED flashlight up to the screen does not seem to matter. I’ll try again in a darker setting (it’s very bright right now) to rule it out definitively but I don’t think the backlight is affected (you can see a slight glow in the dark.)

I already reset the PRAM.

I already reset the SMC.

I already reset the PMU.

I already attempted the MBP pro video update http://support.apple.com/kb/TS4088 which said it is not supported on my system (I was pretty sure it wasn't applicable but worth a shot.)

I don't *THINK* it's the inverter cable as wiggling the display lid does not APPEAR to affect it, which leads me to believe the cable is still flexing without a problem.

Doesn't seem like the display is bad as it comes sometimes on and the backlight still works, but I don't know. Since the MBP is no longer under warranty, I am not necessarily opposed to getting under the hood and replacing something as long as I know what to replace. The inverter cable looks easy (ish) but I don't know if that's the answer.

Have I effectively ruled out everything other than the display? Any insight?