If you had any more success, it would be great to know which model or method you used. I have a Precision M4400 which is almost exactly like the E6500 and it is working flawlessly with with the exceptions of:
Sleep / Standby
some keyboard key combos
volume keys (show the volume going up and down but the actual volume never changes - maybe this is correct and I need to use a different tool for volume)
I changed out the wireless so it is okay.
My big issue is that the battery is always showing 0% whether on AC or on Battery. Did your battery work fine from the start?
I have a 9 cell battery in the unit but I wouldn't think that makes a difference.
I updated to 10.7.2 but the video just went black like it didn't see the monitor (LCD panel) so I went back to 10.7.1 kexts for GeForce, GeForceGA, NVDANV50Hal, and NVDAResman to get it working again.
What version of the bios do you have? is it A27?
TIA