Thanks for finding that Mark. To me - and happy to be corrected - it looks like the spring is a booster spring above the original spring. The springs in the kit are very silver in colour, and with the low res photo it doesn't really look like a spring, but the colour and size look about right.
I have marked it with the arrow. 
 

You could be correct.  Without a bike to check it on, the "safest" is for me to say they replace the original springs.  If someone comes back and tries that and says the new springs are way too short, then the next logical step is booster springs.  No way in heck they are "top out" springs in my opinion. 

The kit in the article came with new short top out springs...  kit was for for early AT/CT which had top out springs... as well as a pair of longer springs. 

That picture is actually easier to see than the original tiny one in the magazine. 

Here's the kit used in the article. 

 

Dug out both the kit and separate booster springs to check size - they arrived at different times but from memory thought they were close. Booster springs made by Circle industries. Both sets of springs approx 130mm