Hi DrPyro,
Im pretty much done with this project. I wanted to paint the mdf box they are mounted on (especially since my lazy butt put a cup on the wood while I was watching a movie and it left a nice little ring in the wood

) but I dont have a place to paint it.
I can take pics when I get home. I'm waiting for my projector so this box is sort of just hanging out in the middle of the room.
I got rid of the fans all together. a 2500+ barton at 12 x 200 and an nforce2 (which gets very hot, dont care what all the cooling-the-nb-is-a-waste people say) are in the loop. Was going to add a 9600xt but I didnt have the time to make another top for my maze4 GPU block so it could be mounted with the barbs pointing towards the end of the card, rather than towards the top. My microatx case gives literally about 7mm of room between the top of the AGP card to the top of the case so I couldnt bend tubes over the card, I wanted to bend them around the end and to the nb. Sorry little OT

But with the barton and nforce2 on it temps were right at 50c and 30c with a 25c ambient with a full load 24/7 (FaD running 24/7). Thats completely passive on the towers. I have 3 60mm fans undervolted to 5v in the case (2 in the PSU and one exhausting). I doubt a 24" or larger one would have much trouble cooling your system completely passively. These are much more efficient than the reserators, the ID is much smaller but the actual surface area the water goes over is much much more because of the internal fins.
Using the towers is pretty straight forward. The mistakes I made were trying to pump the water down the coolers which trapped huge amounts of air, and not really deciding on what pumps I wanted to use. originally I tried a mag3 but it was too loud, then I tried a single 1048, that was too weak, then I tried 2 1048s which was perfect but you guys are gonna laugh when you see the ClusterF* of the routing job I did inside the MDF box to fit the two pumps in there.
Someone mentioned the dual pass Tranny coolers before, I have never had one in my hands so Im not sure about their design. I dont know if they are the same as a single pass (Just a tube with internal and external fins) or they actually have a divider in the middle so it forces the water all the way up then all the way down. It might be ghetto like the reserator where the inlet and outlet of the cooler are just right next to each other. If its a seperate path that'd be awesome, else I wouldnt touch them.
I thought of putting my T line some how at the top of the towers. It would be much much easier that way. With just the T line at the inlet of the first pump it takes forever to fill it. I have to fill the T line, move the box around to get water in both pumps and in some of the tubes, turn it on, wait for the pumps to cavitate too much, fill the T line, tilt the box around, etc etc etc until the towers eventually get full and spill over then its easy. I didnt put the T line at the top though just for aesthetics.
I'll be sure to post final pics when I get home tonight.