I have a 1985 MB 300SD. The car is from Florida originally and it never had an engine block heater installed. This morning it was 8 degrees outside and my car was not happy. It finally started, but if I am going to continue to drive it in the cold weather I want to get an engine block heater. Is there a universal block heater that does not involve removing the allen bolt and inserting the block heater or do you recommend that I get an MB block heater installed in the car. How difficult would it be to install it on the car?