Not sure how different my 85 CDN car is different from Euro or even U.S. but I have had the plugs changed twice with no problem. They didn't access the panel through the firewall either. The hose going to the oil cooler just needs to be moved to get cylinder 5.
If you don't find your U.S one call me.

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Had Enzo been a gentleman...The greatest cars on the planet would have never existed.

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