A Thought Experiment

Let's say that you are the cynical and secretive human interstellar government of a few hundred years hence. (Not too much of a stretch, yes?) You're not actively evil, but you're perfectly willing to do nasty things (or, though inaction, allow nasty things to happen). You're also in a state of war, and have been for some time.

What you need to do now is to plan a secret colony. For some handwave-y reason, hollowed-out asteroids, other kinds of space-based habitats, or anything involving non-Earthlike worlds is out. It has to be a shirtsleeve, dirt-farming colony, as God and Robert A. Heinlein intended.

Now, for good and sufficient reasons, you need to equip this colony with a lower tech level than they're used to. You can either pick an 1850 level, or a 1970 level. Other than pure "screw with the colonists" reasons, can you think of a reason not to pick the 1970 level? (They'd be, as far as I can see, of about equal difficulty, since all of the items in each package would have to be created from scratch in either case.)