Thanks, Jeff, that's just what I needed. You can tell I'm very new to Sketchup. I used your idea to push pull from left to right instead of bottom to top. I'm interested in viewing the tutorial you "forwarded" me involving a solution using "follow me", but the tutorial wouldn't show up on my computer (even after a Flash Player update).

Friends, I'd like to recreate this wheel well in my F1 car using the joint push/pull plugin (the wheel well you see in the picture was created with the "intersect with model" tool, very cumbersome). Everything seems to be going well until I pull the rectangle from the flat, bottom side of my car to the curved, top side of my car. I can't get the rectangle shaped extrusion to make a "hole" through the top of my car. The pull goes through the top of the car but the top of the car remains a clean surface. Can anyone help?