Dumping fuel

Okay truck was dumping fuel out of the tailpipe. Had to replace the spider fuel injection system. Had to have the truck towed home because my mechanic said not to drive it like that. So got someone to tow it home and was very specific about my mechanic saying not to drive it with it dumping fuel like that. However the person just ignored what was said and had is girlfriend drive it from my mechanics to my house. Which is about 6.2 miles. Anyway I took the top of the motor apart and replaced the whole spider fuel injection system. Put it all back together, drained the oil (which smelt like straight gas). Anyway now it is back together and starts but runs real rough and got fuel dripping out the muffler. I know that he probably has my new plugs fouled out, but how do I get the fuel out of the muffler and every where else it is not suppose to be? And how to I check everything to make sure it is all clear before driving it? Been down for a while now and really need to get back on the road ASAP.