Change One Image To 27 Different Images

Im going to make a javascript for changing alot of images. But im not
sure how to do it., where to start..

Ok, first.. this is the isue.

I have 3 images(I call them 1a-3a).
when u click on image 1a u change" image x" to image 1a
when u click on image 2a u change" image x" to image 2a
when u click on image 3a u change" image x" to image 3a

So far Im in the game. But..

Then I have 8 other images(I call them 1b-8b).
So if u click on image 1a u change "image x" to 1a. Then if I click on
image 1b I want image 1a(the changed "imagex") to change.

(click on 1a-3a and change "image x"--> click on image 1b-8b -->
change the images 1a-3a) Messy? I know.

<tr><td>
[1a.gif]-[2a.gif]-[3a.gif]
</td></tr>

<tr><td>
[1b.gif]-[2b.gif]-[3b.gif]-[4b.gif]-[5b.gif]-[6b.gif]-[7b.gif]-[8b.gif]
</td></tr>

<tr><td>
[image x.gif]
</td></tr>

This makes the possibilty og 27 different images(hm.. i think

Do anyone know how to do this or hav anyone done something like this?
"Imagex" is a Box and the 1a-3a changes pattern. The other 1b-8b
changes color. SO it should be possible to first change pattern, then
change color on the pattern u choosed before.