I am in the process of re-building a 67rs, pretty much started with a bare shell. No wiring no heater parts etc. I have located the heater box that goes under the dash and on the firewall. I am not wanting to put a heater control unit in the dash, as I will probably be putting gauges in that slot. My question is, since I want the defrost option can I run the blower motor with a simple toggle switch by wiring it directly to the blower motor, or do I need to use some sort of relay also? Thanks for any replies.