Removing the radiator is not required but I would recommend it because the extra room is more valuable than the effort of removing. Since your van is a 5 speed, there will be no transmission coolant lines to deal with. All you have is the radiator hoses, two lower mount nuts, and the single top mount bolt. Of course there's the coolant mess to deal with, but usually not so bad. If it's not due to be replaced you can always catch it in a clean drip pan and pour it back in after. Tim