There is a primer at the filter housing, but he'll be pushing forever to get it out. Id just drain the tank, refill it, add in some Powerservice,Stadnyne or sometype of additive, then maybe change the filter towards the end of the tank......I did a search and most of the guys are saying to just pull as much gas out as you can and fill the tank up with diesel and add some diesel fuel lube. Then drive it lightly.
I think there is a fuel primer lever some where in the engine area. Whouldnt that help by opening this and letting some of the gas out and fill the line with diesel. etc.....
sorry for being so short, the guy just did it an hour a go and needs the truck in the morning for work to haul some loads.