Magento - Show "Up-sells" thumbnails with grouped product thumbnails

I want to show the thumbnails of the "up-sells" products with grouped product thumbnails, with a link to the specific "up-sells" product.

It will be used like a color selector (for t-shirts for example).

This picture explain a little bit how should be my screen...

http://www.fragento.org/images/fbfiles开发者_开发问答/images/produit_groupe.jpg

Thanks a lot.

---

If I am understanding the question correctly you could check to see what type the product is and then change the following

<?php echo $this->helper('catalog/image')->init($_link, 'small_image')->resize(125)

to

<?php echo $this->helper('catalog/image')->init($_link, 'thumbnail')->resize(125)