vacuum heater control box PSA

On Early A Bodies the part # is 2096084 and there are only two wires that connect to the male terminals on raised portion of the a/c heater control box. One to the heater blower motor and the other to the fuse box.
The new ones have three terminals. For those who may have been inside either a newer NOS unit or the replacements, which 2 of the 3 terminals should I use?