Toyota Repair: 1992 4 Runner, head gasket problem, toyota v6

Question
My 92 Runner is all of a sudden running hot.  I had the radiator replaced a year or so ago, along with the water pump and thermostat.  The temperature is fluctuating from normal to hot, and I can smell coolant faintly.  I cannot find any leaks.  Do you think it is the thermostat, or maybe the heater core?  Where is the heater core located?
Thank you for any help you can give me.  I have not really had to work on this rig much, so I am not very familiar with it.

Answer
Brian,
Sounds like a head gasket problem. Its common on older Toyota
V6 engines. Make sure the radiator is full, if not it will run hot.
Take the radiator cap off when the engine is cold, start it up and
watch the coolant, after it warms up the coolant will flow in there
and slowly start to come out of the top, if it starts shooting out of there and the needle steadily keeps rising then the head gasket is
bad.

good luck,
let me know

Tim