Greetings . . .

To service that spring you'll need to take the back seat rest out. Leave the trunk closed. With access from the front you should be able to a put 3/8 threaded hook on to the spring. Then you can pass the threaded end through a hole in a piece of steel flat stock and place a nut on it. The flat stock will sit across the box that surrounds the spring. Now you can tighten the nut until you take the tension up off the pin so you can safely to take it out - and then you can put in the new one.

regards,
stock49

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