I'm collecting the parts to do this in my Boxster. Picked up a matte black defroster switch on ebay for $12. This guys mod
clicker gave me a better idea on how to wire up the led status light. I plan to use a 2-pole reed switch to activate the remote and the defroster switch led separately (rather than his transistor circuit triggered by the remote led). Power will be from the remote 12V battery to keep it self contained. I'll post some pics when the project is complete.
Project completed. See my DIY post here :
http://986forum.com/forums/diy-project-guides/45508-yet-another-garage-door-opener-install-post341122.html#post341122