i think the tab ta78w72 is talking of is the linkage for the column safety switch, it it will have a hole in it for a 1/4in rod to go through, best thing to check is that it is pulled up as far as possible, or go inside and the collar that moves behind the steering wheel without moving the steering wheel is as far counter clockwise as possible, your other wire might be some sort of accessory feed, so to test that without having to unbolt anything from the starter to see if it is the problem, secure it to the pos side of the battery.....if it does in fact allow your motor to crank over, find out what it goes to and see about fixing it...as for your turn signals, your key must be on, and sometimes just replacing the relay helps......do you have marker lights when the lights are on?