Hi man, i have the same Latitude e5420 , after 3 weeks i got a fully working install Lion 10.7.2
Disable 1394 port in bios and ExpressCard set boot for minimal
just use iboot (chameleon, stolen and rebranded) from tonycrapx86 blog with last chimera (chameleon, stolen and rebranded) edition don't use Graphics Enabler
after install boot from iboot (chameleon, stolen and rebranded) again and add some kexts to /S/L/E/ and use MultBeast for Lion and make smbios,plist Boot.plist files
the kexts used was:
to boot
FakeSMC
IOAHCIBlock
AppleCPUPowerManagement patched With speed_stepper_lion_1072(google it) if cannot found use the NullCPUPowerManagement instead (but no Sleep)
Mouse and Keyboard Both works but mouse don't recognized as a touch (no gesture working ) Google for Synaptics Keyboard Gesture 32 64
AppleACPIPS2Nub
ApplePS2Controller
Audio (Semi Work, Master Volume doesn't work and some glitches at playback music, i can't get intel HDEF working need DSDT hacks and i didn't try )
VoodooHDA 0,2.72 from multifail (delete AppleHDA.Kext to avoid Kernel Panic)
try AppleHDA Patched For Lion
Use BCM5722D Kext
For Battery
Voodoobattery kext
Onboard Bluetooth No kext needed
Onboard Webcam No kext needed
Onboard wi-fi Not work use a USB or change onboard card
Get Almost Info and next at this sites:
http://www.kexts.com/downloads.php?do=file&id=1578OnBoard Ethernet
InsanelyMac or OSX86PC
tonycrapX86
http://www.osx86.es