I have a 2 lever in my 63 and im in the process of ordering an a/c kit for it from Classic Auto Air. In the installation manual for that kit it converts the 2 lever to a 4 lever. I dont know exactly how much work it will be to modify. I dont know if they you can get the parts you need from that website (without buying the complete kit) but its probably a good starting point. Good luck

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