Car shuts down when temp. read out reads 180 or higher. Have to wait 15-30 min before it will start again. Have already removed thermastat and wiried cooling fans direct? Any help??

I'm not sure if the 1989 Cadillac eldorado has a heat valve in the radiator,cz some does.
But if it does I think you need to check it first, cz these valves keep closing in many cars which stops the water from running in the radiator ans raises the heat.
I hope that was helpful, I know I'm not the best in mechanics but Good Luck