Should be spring side down most engines. The bi metal parts that cause it to open are generally on that side and have to be exposed to the coolant so it operates at correct temp.
By the thermostat
Vrey carefully
In the motor.
to keep the hose from collapsing
Stuck thermostat, scale build up in the radiator and engine block, radiator cap not holding correct pressure. or it could be your headgaskets
near the thermostat housing
Usually at engine end of upper radiator hose in housing
located n housing at end of upper radiator hose.
A Cadillac Deville can be purchased at a Cadillac dealer.
t.h.440/ early 4t60
p205 70/r15
could be your thermostat or you have no antifreeze coolant or your water pump is going bad