It's only radiator cap is on the coolant reservoir.
Look in the removable housing at the engine end of the upper radiator hose
The radiator does not have a cap, instead, the coolant system reservoir is also pressurized and the pressure cap is on the reservoir.
If Im not mistaken, the Pressure cap for a Saturn is the twist on cap on top of the coolant resovoir, if the cap say under pressure then that is it and to add coolant to radiator you fill it thru the res.
The radiator cap is on the coolant reservoir, which is mounted on the passenger side fender for S series Saturns.
Saturn radiators don't have caps to check and add fluid to the radiator you open the overflow tank and add it there
You fill it though the resivoir cap
A 2000 Saturn LS2 with the V6 3.0L engine requires 5.0quarts of engine oil.
That's a "dealer item", meaning that you'll need to either go to the dealer or a wrecking yard.
The battery type foe a 2000 Saturn LS2 is a 12 volt side post. The group size of the battery is 75.
the ONLY access to the radiator is the overflowreservoir on the passenger side it has a big black cap and its right above the windshield washer fluid tank
The V6 engine in a LS2 has a timing belt with replacement intervals at 100k miles
More than likely it doesn't have direct access to the radiator via a radiator cap. so the high pressure cap would be on your coolant reservoir should say 16 or 15 psi on it. if you need direct radiator access might consider taking loose the top radiator hose.