Thumbnail links to display fullsize on item page (Add previous to thumbnails)

I have scans of old handwritten notes that are a part of a single item. Each image has text that I would like to associate (show) with only a single image. So I have two questions:

For an item with multiple images, is there a way to make it so that when I click on one of the thumbnails it shows that image in 'fullsize' and adds the image that was showing in fullsize to the thumbnail list? This way I would be able to "flip through" all the images in the item while still remaining on the item page.
I was thinking this should be doable with some PHP but I'm really not sure where/how to start. I was thinking along the lines of if I could capture the ID of the thumbnail, reload the page, and then use it an if/while loop similar to the current one used to show.php.

My second question is would it be possible to show only the relevant text pertaining to the image that is 'fullsize' while hiding the rest? My thoughts on this were if I added each separate text to an additional Description field, then use an IF statement to show, for example, only text from the 3rd description field. Is it possible to filter like this on multiple instances of a single field?

I hope I was clear enough in describing what I would like to do. Any help / suggestions are very much appreciated. Thanks!

Sorry, forgot to mention that I would still like the 'fullsize' image to link to the 'actual size' image.

This is exactly what I'm trying to do, but I'm not understanding how they did it.

http://lincolnat200.org/items/show/65

Have you opened the code in Firebug to examine the HTML, CSS, and Scripts that make up the item/show page?

What you are asking for is complicated. This site was customized by a designer-developer who worked with the Newberry and Chicago Historical for about a year to create this website.

Alternatively, you could also try adding a lightbox, which is different but might achieve a similar effect.
http://omeka.org/codex/Adding_LightBox_to_Omeka

There has been some discussion about using lightboxes in the forums lately.

Hi Sheila,
I've got the image swap working, it was actually easier than I thought.

Thanks for the lightbox suggestion, I'll check it out.

Do you know if the second part of my question is possible? Is there any identifier that Omeka places on the metadata fields if you add an extra description for example?

Again, thanks for your help.