hey I really desperately need to repair my heater in my '56 chevy sedan. it's my daily driver, I currently have the rotten heater core bypassed and the morning weather's in the mid 30's and dropping. new heater cores are not very cheap, for not a whole lot more, around $500 I can get a 'direct fit' (mostly direct fit) underdash kit from Vintage Air or Classic Auto Air, maybe some others; both of which offer A/C, heater and defroster. I already have an A/C system setup and running that I built into the center console I made, so I'd just need to route compressor lines and recharge the system. question is, is there any difference between the vintage air or classic auto air systems? I haven't really heard anything bad about either one from people that have owned them...any of you have any feedback?