Did '71 Come With Accessory Ignition Switch

[Gregski]

working on a '71 GMC basket case and not sure what the ignition switch that's currently in it came out of, it doesn't seem to have an accessory position just what seems like OFF, ON, and START. I mounted it in the dash next to the heater. Question is, is that the right switch for the truck or did they have accessory in 1971? hope this makes sense,

I am asking because my alternator is showing a constant load of about .88 amps even with the truck off and key out of the ignition, this needless to say drains my battery, I am running a one wire setup with the regulator deleted, I have the same setup on my '74 and that works great