Help with porsche 550 tut

Im doing the Porsche 550 tut (http://perso.wanadoo.fr/speedtiti/tutoriels.htm)
And I don’t understand what he is trying to say in this paragraph:
“-To make realistic cuts out, select each hood edge vertice and extrude them downward once of 0.01 BU (Blender Unit) et a second time of 0.1 BU (Shift+Ctrl). Select the new part you’ve just created and duplicate it (Shift+D), separate it [P key] and join it to the car [Ctrl+J]. Do the same for doors.”

I think I got the extrusion part right, but i don’t understand everything after that. What exactly is he saying to do?

Thanks

It seems that he is extruding the hood edge and he wants you to select the part you extruded and duplicate it then separate it. Then he wants you to take that shape and join it to the hole where the hood would be on the car. If you looks at the second image down from that paragraph, you can see the hood hole on the car now has an edge that goes into the hole. Compare it to the image just before the paragraph.

I would say that’s a long way to do it given that the hood was separated from the car in the first place. You should get the same results if you select the edge of the hood hole on the car and extrude down 0.01 then a second time by 0.1.

Ah, thanks very much! I get it now.