You won't get an appreciable amount of coolant out of the block putting a heater in an EJ series engine- I can't imagine the SVX's motor is all that different. I highly recommend a 1/2" drive hex socket on a 1/2" breaker bar with about a 3 foot length of pipe if you don't have air tools. The plug isn't in there all that tight on its own- it's the thread sealant that makes it stick so damn well
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