fryfly,

Not only will the plugs stick out the side, but the hub might as well. If I'm not mistaken, the 3W-100 is about 7.5" long, this would push the hub about 1" out in front of the cowl unless you cut the firewall off and shorten it. The full scale Giles is a small plane, so a 35% version would compare in size close to an Extra of about 31%.