meitzner

I recently bought a 97 civic. When I bought it, it already had an aftermarket stereo, however I'd like to put keyless entry into it, and I'd prefer the OEM system (which I understand goes through the factory stereo). So, if I buy a factory radio and remote FOB (cheap on eBay), and a wiring harness to supply power to the factory radio, is there any reason why this wouldn't work? Are there some radios that have keyless "built in" and others that don't, since some I see have big green connectors on the back (15 pins or so) and others have little green connectors (only 4 pins or so)? Do I even have to plug in the green connector since most instructions don't ever say that you do (although I don't get how the lock/unlock signal could ever get to the doors if only power and ground are connected) I've also heard that some remotes only work with some radios based on FCC #'s, any ideas? I've also heard that you need a special code to activate the radio...any idea whether this goes for just using the radio for keyless entry, or whether the code is only needed for listening to music - also since i guess programming these years of keyless requires pushing some "hidden button" on the radio, am I going to need the code after all? Is there a way to get this code without paying Honda dealers $80 for it? Any answers to any of these questions would be helpful, thanks.