Does anyone know if the newer model kenwood brain units (ie kvt-817, kvt-7017) are compatible with the previous model touch screens (ie kvt-814, kvt-7015)? I've seen a few of these brain units on ebay and would like to upgrade my system functionality without having to replace everything. The monitors look like they have the same hard buttons and the connector looks the same but I'm not sure if they will work. If anyone has any info please let me know.