I thought it was two separate attachments, one for carrot juice and one for cider. But looking at it more closely, I see it’s actually just one press for either.
It looks like after you juice the carrots (or apples) in the Vitamix container, you then fit the bag over the top, then dump out the juice (the bag catches the pulp). Then put one of the perforated square plates down inside the bottom. Then place the bag with pulp on top of that. Then place the second square perforated plate on top of the bag. Then put the screw on, and turn the wheel to press.
Here are the official instructions from the manual:
Cut fruit into pieces as long as they are wide. Cut pieces so that they are roughly identical. For best results, fill the container full.
Clamp on the action dome lid, making sure the funnel top is in place.
Turn to speed setting 7 and 8, flip forward and reverse once or twice. While running on forward, start pushing the fruit down using the tamper through the action dome. The funnel top of the action dome will allow you to push just far enough without getting the tamper into the blades. Keep pushing down in the center to get the fruit chopped and circulating. Use the tamper to loosen pieces of fruit that may be lodged to the sides.
Stop the machine and remove the action dome lid, then pull the nylon bag well over the top of the container like a stocking cap, and invert the Vita-Mix container over a pan or bowl, shaking and tapping sharply, to dump the contents into the bag.
To Extract Juice
Unwind the screw device from the lid and wash all parts of the press in hot suds, rinsing thoroughly. Lubricate the screw with vegetable shortening, including the end. Drop one metal platform into the bottom of the container, hollow side down.
Fit the bag full of pulp into the container, open part up. Shake the pulp down solidly into the bag, or push down with a spoon, and fold the top of the bag over tightly and smoothly.
Place the second metal platform, hollow side up, on top of the folded top of the bag. Push down enough so that the lid with the screw device can be slid across and clamped on top of the container at right angles to the container handle. Fasten securely in place by matching the curled edges. For each usage, lubricate the stainless steel screw with vegetable oil or shortening at all points of friction, especially where it inserts into the round fitting on the platform.
Start winding the screw device downward by spinning the wheel between your hands. Screw should insert into the round fitting on top of the inverted platform. As you work it downward, the press is pressing the juice out through the bag. You’ll find that you can drawing juice off through the spigot right away. By spinning the wheel between both hands you’ll be able to exert great pressure withe very little effort. When you have worked it down as far as possible, if you wish to allow it to sit a few minutes under pressure, even more juice can be extracted. You’ll find more juice in the bottom of the container below the level of the spigot. So be sure to remove container and with lid off, pour out as from a pitcher.
Remove the juicing apparatus by reversing the procedure, winding the screw part upward until the top can be slid off the container, and inverted platform removed. Remove the pulp, wash out the bag, and all other parts. With a little practice–more, better and richer juice may be extracted with speed and efficiency.
[edit: for some reason the formatting in my post doesn’t match the the instructions. After ‘To Extract Juice’, the numbers should continue from 6 to 10]
also from: http://www.ehow.com/how_7570593_vitamix-press-instructions.html
But if you already have a Champion juicer, I’d stick with that.
If you really want to extract every last drop of juice from the pulp, then instead of the Vitamix press attachment, just scrape the pulp from the Champion juicer and re-press it through a chinois and/or a cheesecloth.
Hope this helps.