My Dad's 1984 Ford Bronco II with the V6 was the worst I ever did. To get at the plugs near the firewall you had to go in thru the wheel well. Ford actually had a spot marked on the wheel well liner where you cut out a small rectangualr area. Plug was directly behind and nearly a straight shot to get at it. When you were finished, you mounted a cover patch (Ford item) over the opening with some self-tapping screws.