Hello, welcome to the BB.
Come on up to the 'Spider' section - more "traffic" there so folks can chime in with ideas. Here are my ideas:
1) clean all electrical connections, grounds, and the fuse box contacts. Might be a good idea to install all new fuses, too. Who knows how old the ones in there are - seems like it'd be cheap insurance to have new fuses.
B) contact BB member PapaJam. Ask for a copy of his color coded wire diagrams for your model Alfa. Include your email address and he'll send you some .pdf files that will make chasing Alfa electrons much easier. I took a copy on a flash drive to an office supply store and had them print out color copies on 11" X 17" paper then laminate them. Great for use in the garage.