[Ian W.]

If you're cutting a piece of metal from one big rectangle into two smaller rectangles, go for it, because you're not doing anything that would be designing or whatnot. I mean, if you have a big piece of aluminum, but need a chunk off of it for something now, and you're saving the rest for build, then what's the big deal?

However, if you're doing any actual design, like figuring out what kind of base you'll want (I don't know how you do that before kickoff, unless you're RAGE), then no, you can't start prefabricating parts.

There's no real option for this, so I didn't vote above.