It probably fell through. You should still be able to pull the HU. You'll either need a set of real radio tools, or do a DIY like I did with a dremel and the steel strips from a Pendaflex folder. Take a look at Jeff Bipes page for some basics.

http://mk1tt.montebellopark.com/fabup.html

 

Meh. $4 at walmart for a pair of keys.

 

I tried using DIY keys but nothing budged. I ordered keys off ebay ... hope they work

 

They should, the theory behind them is that they lock into place but while doing so compress one of the 'spring clips' on the lower side to allow it to slide out. If something is jammed in there you may be able to push the keys in and have it fall out as there is room for it to drop, failing that you may get under that piece of card and still allow the clips to compress and pull it out. I should thing you will be fine, i had mine out only the other day and had a mooch at them

 

I stole my keys from the douches that ripped me off on my clutch job.
Made me feel better about getting bent over w/out lube.

If you are anywhere near NYC metro you can use mine.

 

Heres what I did for a similar situation..

If you are able to get the one side of the head unit out a tiny bit, slide a flat head screw driver behind that side. It takes a little nack but what you are trying to do is pop the entire front plastic face of the head unit off. it attaches to the main radio chasis via this plastic connector that holds the copper connectors (sorry hard to explain).

The head unit face is about 1/2 inch thick, so once you get it off the release pins should clearly be visable.. you can use almost anything to push them in at that point.

Sorry, its a little hard to explain, but basically you are almost treating it like an aftermarket head unit by taking the face off. Dont worry, It snaps right back in and functions fine

Did this on my 2001 Bose Concert I

 

Thanks a lot -- I'll try that when my radio keys come in (the seller shipped it today)

 

Hopefully the keys work for you. If they do, my instructions arent really needed, however if you find when you insert the keys into the holes the radio still dosent budge then one of the release pins is fubared (that was my problem) and my alternative method will work..

 

Thanks everybody! My radio keys ($5 off eBay) came in and when I pulled the radio out, the credit card piece fell out on its own

The previous owner had Sirius installed and it was hardwired to the Concert Head unit, so I snipped that off.

 

good stuff, always nice to see the cheap fixes work