Products "sort by model" problem

Ok, I spent hours searching through the posts about sorting but I can't seem to find a solution to my problem.

I believe I setup everything correctly for products to be sorted by model.

This is what I get:
ABC10
ABC12
ABC2
ABC3
ABC4

But this is what I want:
ABC2
ABC3
ABC4
ABC10
ABC12

I believe this could be a problem caused by SQL. Or am I missing? Has someone already fix this problem? Model name cannot be changed (there are too many) and I tried to explicitly give a sort order to the products in the category but it seems Zen Cart just ignores it.

Any help is appreicated, Thanks!

Alpha sorts are based on numbers and characters logic ...

To get this display:
ABC2
ABC3
ABC4
ABC10
ABC12

You would need to use:
ABC02
ABC03
ABC04
ABC10
ABC12

So that the numbers do not sort as:
ABC1
ABC10
ABC12
ABC2
ABC20
ABC21
ABC3
ABC4
ABC40

Thank you for the reply.

I can't change the model number since there are way too many (10,000+). Is there anyway I can overide the default sorting method I defined in PRODUCT LISTING by the sorting order I explicitly defined for each product in the category? (The listings on the admin side works perfectly)
Thanks.

Ok, I think I figured out this....

in the file includes/index_filters/default_filter.php
Change:

        case 'PRODUCT_LIST_MODEL':
          $listing_sql .= "p.products_model " . ($sort_order == 'd' ? 'desc' : '') . ", pd.products_name";
          break;

To:

        case 'PRODUCT_LIST_MODEL':
          $listing_sql .= "p.products_sort_order, p.products_model " . ($sort_order == 'd' ? 'desc' : '') . ", pd.products_name";
          break;

(For sorting by MODEL only, for others, modify the related "sort-by" right below the code I mentioned above)
The code above allows you to have the products sort order overrides the default sort setting in both ALL LISTING and PRODUCT LISTING. It makes sense to me that if you explicitly give an order to the product itself, it should be made the utmost importatance.