Chevelle electrical

Today I ran into a problem and wanted some ideas. I have a 68 chevelle and replaced plug wires today then decided and needed to work on alternator bracket to align the belt better. So I disconnected battery removed alternator from bracket not removing the wiring . when all done connected battery started car warm up a little and everything looked good. Noticed the headlights on and drivers side marker light loop and all other marker and taillights off. The passenger side both lights are on but really dim . The driver side has just low beam on and looks normal. I disconnected headlight switch and lights are still on all of the time. Any ideas of were to start would be great