A qusetion about a 1986 ford f350?

I have a 1986 ford f350. It will run but it runs rough & puts out alot of white smoke. It has dual tanks with electric fuel pumps. It's a 7.5L 460 & it has a carburetor. I have never seen a carbureted vehicle with electric fuel pumps myself.(must be another one of those great ford innovations) I noticed after it ran it would flood itself out causing it to die. It eventually gets fuel in the oil as well. I was wondering if anyone has any ideas about how to fix it. I have had the car rebuilt & the safety shut off Switch by the kick Panel does not work proper so & the fuel pump runs all the time. Please help with any Information. I am about to start driving here next month & it's the only reliable vehicle that I might have If I can get it running. Thanks for the help in advance.