I have purchased a '84 GMC with a 6.2 in it. It has been sitting for about 7 years. The PO said he drove it to where it was sitting. He said it was getting hard to start because the glow plugs weren't working properly. He had other trucks and just never drove this one again. I am very familiar with getting an old gas truck started after many years, but not so much on the diesel. Do I need to drop the tank and clean it out, or pump some out and if it looks good, give it a shot? What else should I do? I don't want to create more work for myself! Any advice will be greatly appreciated. Thanks.