Is there any way to add factory remote keyless entry to my 1999 chevrolet tahoe police model. I have checked it for the system and it does not have it. It has the power windows and doors. Also how hard would it be to install the factory overhead console. Mine doesnt have one because there is no rear air. I want to delete the rear air controls and maybe modify it to house audio controls. If I can install rear air, I might just do that. Any help or ideas would be appreciated.