1999 Chevrolet Silverado 4.8L V8 2WD

After driving the truck, I let it sit for approx. 20 - 30 min's and then have to let it turn over for about 10 sec's before it will start. Is this a possible fuel regulator problem?

check the fuel pressure regulator, remove the vacum line and look for evidence of fuel in the line.

Turned out to be the fuel pressure regulator. Look at my thread for the fuel gauge and the explanation is there for my story.