anyone able to tell me where the tachometer wire comes out of the bulkhead on the engine side of the firewall and what color it is.....its an 84 grand national.....trying to hook my factory tach back up and cant locate the pin location on the bulkhead. Also before I take the speedo back out can you switch between 6 cyl and 8 cyl on a grand national dash to make the tach read properly or do I need a module. I know where to get them just wasnt sure if these had a switch on the back like the cutlass rally pack.
