Some years ago I scratch built an Imperial Guard troop lander. Then I used balsa wood to make the main hull chassis, and hung thin plasticard on it as a skin finish. This time I bought some heavy plasticard and used it to make a monocoque hull with no chassis. This was an error. Despite my best efforts thee plasticard warped slightly under the impact of the cement. It wasn't bad enough to abandon but a slight warp brings back issues as detail is added.
A chocolate mousse container had just the right rounded rectangular cross section and deliniation for the nose cone turret.
I added a heat-shield around where the rear where the thrusters tubes would be fixed, partly to look good and partly to hide the attachment point.
At this point, I left the whole thing overnight to dry then sanded down the edges.