I just did the job yesterday and it is a tight fit. If you remove all of the spark plug wires from the cap you can reach it with a socket and an extension. It still is a tight fit but once the lower screw is loose, you can loosen it with a well placed finger tip. Why not replace the cap as well? If you don't remove the spark plug cover be sure to label/mark your plug wires.

or

Disconnect the air hose with the AMM on the back side of the air box, from the box, by removing the two torx screws. Push the hose to the back, be gentle. Now remove the clip on the side of the box (I forget what wire this clip holds) near the dist. cap (also two torx screws) and move it out of the way. Now pull up on the box to release the clip that holds it from the bottom and push the air box towards the cap to release the clip from the inside fender wall. The plastic hose leading from the air box to the grille should release on it's own. If not pull it off from the front. It's durable and only a hose. This will give you plenty of room and can be done quickly.

In the long run I think it's less frustrating to the remove the box.