1991 Buick Century Charged battery now have issues

Electrical problem
1991 Buick Century 6 cyl Front Wheel Drive Automatic

I trickle charged a dead battery on my Buick, now the radio, trunk release, interior dome and courtesy lights and turn signals won't work. The turn signals come on but stay solid, I checked fuses and replaced bulbs to no avail, my friend says there may be a master fuse but I cannot locate one.