I have restored a 81 Cutlass Calais and replaced all sockets. I have replaced the side marker sockets and front turn signal sockets, but when I turn on the park lights the front side marker lights and front turn signal/park lights do not work they do flash when I have the turn signal on (side marker/turn signal). I have checked both flasher in which on is on the upper left side of the fuse panel and the other is on the lower right side of fuse panel. Curious about what other grounds to check. I see the ground wires up front close to the head lights are screwed in. What can I check? No forum seems to be of any help.