[HALP!] How to assemble ripped LegendOfMana backgrounds?

[pgmana]

Hi there,
I've been lurking the site for some time, finally i've found a project that's worth a "first topic"!

I'm ripping Legend of Mana (PSX) backgrounds, after A LOT of work i've manged to hack the iso, crack the compression, and grasp the raw graphical data.

I'm using TiledGGD to extract the graphics: i've a bunch of raw data files, containing the graphics, the palettes and other useless data.
I save the graphics with every possible palette and get for example this:

http://pgmana.altervista.org/hidden/lak_...s.dec3.png

from this you can assemble for example this:
http://pgmana.altervista.org/LoM/lak_upst.png

( If you dont see the pictures, copy-paste the URL in the urlbar of your browser! )

Now, what i'm asking for is an idea ( A tool or a routine would be the ideal ) to assemble those files automatically, or at least help me easying and speeding the process.

I have 490 raw data files, in everyone there is between 3 and 15 palettes, that makes THOUSANDS of "puzzles" to assemble...
Also note that the one i posted here is by far one of the easiest ones.

Doing it manually would take me years... T_T