ActionScript 2.0 :: Build New Array From _width Values In Loop?

I have a bunch of thumb mc instances on my stage, using the same mc symbol. They're all sized differently so the widths(which are same as heights) vary.I want to be able to access their width value from an array independent of all the scaling I'm doing with rollovers. That is, I need to have each mc instance's original width accessible from anywhere in my code.The simplest way to do this is to hard code an array, like:

var Twidth:Array = new Array();
Twidth[0] = "33";
Twidth[1] = "45";[code]....

But since I have 22 thumbs and several portfolios, and want the option of changing their original sizes on the stage, I want to create the array above on the fly using information in a loop. For instance, I already have a loop in a function called generateThumbs(). Here's what I've tried:

for (var i = 0; i<total; i++) {
Twidth = new Array();
Twidth[i] = this["thumb_mc"+i]._width;[code]....

for trace on the first method, replacing 'i' with the key I want (Twidth[2]):

undefined
undefined
45
undefined
undefined

As you can see, this gives me non-indexed non-delimited value for the whole loop (the actual in my real movie is 22). There's no length or array because its actually just one value. Entering a number in the key will display a bunch of undefined with one defined. I have no way of extracting that one key without getting all the other undefined values.my question is: How do I put 'this["thumb_mc"+i]._width' values into a loop with each value indexed for the rest of my functions to access?