As promised, I've uploaded the article for the Duramax 6600 Performance Pull-Off from October of 1999.

The linked article covers the performance testing we ("we" - myself, another automotive writer and full logistical support from GMPT and the local Chevrolet dealership) did for these trucks right here in Montana. The testing we performed here in Montana included performance/drive-ability evaluations using a 10,000-lb trailer on a long 6% grade from a standing start - among several other tests. We also performance-tested/compared these prototype trucks against a new Ford Powerstroke and a new Dodge Cummins. This is the very first-ever non-GM test of the Duramax 6600 powered pickup trucks.