In my opinion the factory heater box/evaporator is superior to aftermarket systems like Vintage Air. I also see no fault in the rv2 compressor. As far as cusom lines are concerned you can but the fittings and rubber, mock it all up, mark it and take it to a shop for crimping. They make a r134 expansion valve, replacment drier and condesor for your car. I would call a few vendors and check availability before making any major plans.
