I am trying to install a backup camera in my trunk lock keyhole just like this, same car - 2007 Mustang:
viewtopic.php?f=33&t=24868&p=186793&hilit=keyhole#p186793
What camera would fit?
I picked up a Boyo VTK-350 'keyhole' camera but it is a little too wide for the hole. 
Those are all over eBay for like $10-$15
I picked up a Boyo VTK350 and an Audiovox CMOS-2 in hopes of dropping them in from the outside and threading the collar onto the camera from the inside.
Both are too large. The Audiovox is very close, but still about 1-2mm to wide. I guess I will need to build a bracket to mount it from the inside.
What about shaving the edge on the audiovox ? or is it the threaded part thats too big ?
What about shaving the edge on the audiovox ? or is it the threaded part thats too big ?
It is the threaded body that is too big on both of them.
The Audiovox is a closer fit, but still off by a few mm.
Gotcha yeah I looked at the audiovox, its just a little more than i wanted to spend. But I'm pretty sure its about the right size, never actually test fit. Get some pics up of your install when you get around to modifying it I'd be interested to see how you do it.
Hello
What happened with your project?
I'm thinking of something like that and wonder what camera you used that case and if you were satisfied?