Change the fuel pump, change the oil & filter, and do another oil change in about 500 miles. ATF has NO place inside an engine. If the engine was run with the gas-contaminated oil in it, it's already gotten enough of a solvent cleaning, which is what the dummies who reccimend an ATF flush believe will happen. The friction enhancers and various other additives in the ATF really don't need to be in an engine.
Jerry