I have a 1990 firedbird with a 305 TBI engine. Having issues finding out why my electric fan and temperature gauge in my cluster are not working. The fan will switch on when I turn on the air, and my gauge is connected as when I turn on the car it moves all the way up but then stays at 100. I replaced everything but cannot get the temperature switch as I cannot get it off. The new one takes a 13/16th socett but I cannot fit it on the old one. A 7/8ths is to big. So I am figuring it is just rusted but I scraped the whole thing and still the 13/16th will not fit. Any ideas?

 

11/16 fits, i just put one in today

 

if a 13/16th does not fit the 11/16ths will not either. I figure I am going to have to find one of those sockets that addapt but not sure on how good they would be.