car that need the factory head unit

I've been told that their are certain cars that need the factory radio to function correctly. 

Some honda civic, new cavilers,

I know one guy that placed his factory radio under his spear tire connected so he could put an aftermarket in the dash. 

does anyone have a list of problem cars what the problems are and the best way to get around the problems.

Hey Xclusive,

There are more and more that communicate with the BCM thru databuss.  For example ; 02 Envoy, 01 Gr Am, 01 Sunfire, 01 Alero, 01 Impala, 01 Malibu, 01 MonteCarlo, 02 Trailblazer.  The removal of the factory radio in these vehicles will result in the loss of the door chimes and other vehicle systems that rely on the OEM radio. There is also the possibilty of the airbags inadvertently being disabled.

1998 + Honda Accord, CR-V and odyssey ( Canadian spec'd ) have a ground loop that needs to be connected through the factory radio or else the factory alarm/ keyless entry module does not work at all. This is a simple bypass though, no relocation of the OEM deck, just a single wire.

Could someone be specific on the installation of a head unit into a 2001 Malibu,  i have the relocation harness, but where do I actually put the factory unit.  I figure somewhere in the trunk, but mounted somewhere?  All i can picture in my head is a deck laying in the trunk. lol (sort of)

Anyway, any suggestions would be great.  And is there any special wiring tips besides just wiring the relocation harness up?

Thanks