Okay... you make a feature that is, in this case, your entire ship, skinned and everything... you make it passable and indestructable... make sure the collition sphere so that the renderer doesn't make it disapear. then, you make this feature matched by the terrain in such a way that when you walk/build on the terrain it looks like you are walking/building on the terrain... I'll have to make another demo now that s3o's make more sense...
So here's an idea I had for another terrain feature
it's like a chunk of an old platform or station. I figure I could use a model of the Core Antimatter blaster placed around some raised terrain for the dead turret, maybe if i can learn some modeling skills/someone's feeling generous change its texture to reflect age/ damage. The superstructure members would most likely require a terrain feature if they're even possible.