Replacing the mini pci express card

I have a 2140 with a mini pci express broadcom 4322 wireless card.

I'd LOVE to replace the card with something else, namely an intel mini pci express wireless card, 3945 or 4945 series.

Is there any chance such a change would work? Would it work with the LED/hardware-switch? Would it work, but without interacting with that hardware?

Any information would be appreciated.