My block heater is burnt out in my 1990 2 door tracker and it is -30 here (-46 windchill)  I want to try one of those circulating coolant heaters.  http://www.canadiantire.ca/AST/browse/4/Auto/Winter-Driving/WinterAutomotive/PRD~0303294P/ZeroStart+Tank%2BCirculation+Engine+Heater.jsp?locale=en
They are suppose to heat really quick (hour or 2) and then you even have full heat blowing out your heater when you start your vehicle too.   Anyone used one on a tracker?  What size should I get?  Any install suggestions?

I have one of these from Katz on my 3-cylinder Geo Metro commuter car:
http://www.amazon.com/dp/B000BO8X9K/ref=asc_df_B000BO8X9K1867056?smid=ATVPDKIKX0DER&tag=hyprod-20&linkCode=asn&creative=395093&creativeASIN=B000BO8X9K

They make them in several sizes, all you need is some extra heater hose to plumb it into the existing system, drill a couple of holes for sheet metal screws to attach the little bracket. I ran the 110v pigtail out the lower grill opening, zip tied the cord into place. I have an outdoor lights timer and extension cord that I plug the car into at night. It automatically turns on via the timer at 5am. The water temp is about 150degF about an hour later, when I leave for work, real nice when we have a cold snap and the temp drops below 35degF. My heater blows warm air right away, to defrost the windows, and within a 1 mile, the car is up to full operating temp. Saves gas too, because it goes off 'cold start' mode almost right away.