Where do these plugs go?

Being a 74, that first plug could have been related to the seatbelt interlock system. Blue should be hot, and is that yellow going to the starter solenoid? I have a 74 Duster, but that was all changed long before it got to me or I could help. I can get a pic tomorrow of the two plugs that are not in use in my bay. They are right up by the firewall though.

Edit: amazing what gets typed while you're typing!