MAF has nothing to do with the overheating, but I bet you are burning lots of fuel.
Rovers like Antifreeze, then tend to leak more than they use unless you overheat them, they the will cost you more than most want to spend.
Check your Antifreeze level at minimum WEEKLY (yes I was loud there for a reason)!
Go out and buy 2 gallons of premixed 50/50 antifreeze, make sure it says it will work with all types of antifreeze (50/50 because most people will not use distilled water, and will not take the time to mix it properly).
Fill you tank and with the tank lid off and the heater on full blast start your Rover. Fill your tank until it will not hold any more and the heater is actually blowing hot air (not warm).
Shut the rover down, put the tank lid back on and let it sit for an hour or so... go back out and start it again with heater on, run it till it gets hot. Shut it down and let it cool, check the antifreeze level again. It should be at the fill line or above (fill line is basically the split in the tank.
If you still are getting fogged windows you may have a heater core issue.