I ordered a fan clutch today - Oreilly has a Hayden with lifetime warranty for a reasonable cost ($57). Dealer here wanted $180 plus shipping, no warranty, so not going there.
The thermostat is not genuine Cummins, it is AutoZone brand. Said 195 stamped right into the flange. Had to buy their thermostat and cap with the radiator to get the lifetime warranty on the radiator. Autozone was the only place I could find a radiator with a warranty more than 1 yr.
Don't know about the gauge, but it will read 190 - 200 when up to temp ever since I put the new parts in, so I assume it is accurate. Only time I have ever had it go above 200 is when I towed the trailer home and back, well at least after the new radiator and parts.
Jeff