The front and rear valance panels are separate pieces. The instructions call for them to be attached AFTER the interior/engine/chassis assembly is put in the body. I found a way for you to put those two panels on the body before paint and still be able to fit the interior/engine/chassis assembly into the body. Fitting those two panels on before paint gives you a much better chance of getting them all to fit right. You just need to cut a bit of the back end of the chassis off to make this work. See pic.