Truck Repair: m11 thermostat replacement, drain coolant, ftlbs

Question
have a 96 volvo with a m11 cummins,can you tell me how to replace the thermostat

Answer
Drain coolant.Probably will have to remove alternator too.There are 4 bolts that hold thermostat housing on engine.The thermostat housing is squarish with 4 bolts,2 with studs on end & 2 plain bolts.They torque to 50 ftlbs because the go all the way to the block.