Editing led.iff files

Can someone give me information on how to edit the led_xxx.iff files and making them work in the game? I'm trying to edit those cheesy graphics like "noise", "swish", "shhh..." and the like that you see in the stadium and in reflections. Using the 2kx modtool the edits just don't show up at all.

Cheers.

try using the 3DM tool instead, iirc the mod tool can be fussy with those files