Mazda b2000 Engine Idle Rough

My Truck Is Overheating And Idling Rough With A Strong Smell Of Gas. I'm At A Loss Of What It Could Be, The Reservoir Is Full Of...

I Have Replaced Air Filter, Plugs, Plug Wires, Distributor Cap And Rotor. And Changed The Oil. I Am Thinking It Maybe A Throttle Sensor Or...