The gantry rolls in the direction of the wheels. So they'd just pull them back. I figure the platforms that extend out to the rocket, retract into the gantry, then they pull the gantry away. Those old cartoons should be put on DVD or at least re-broadcast.

"Few are agreeable in conversation, because each thinks more of what he intends to say than that of what others are saying, and listens no more when he himself has a chance to speak." - Francois de la Rochefoucauld

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Poser 12: Inches (Poser(PC) user since 1 and the floppies/manual to prove it!)