[JoeG]

Hey Paul,
Thanks for the link. That thermal switch was just what I was looking for.
As for cutting the lexan, I drilled 2 3/8 holes to remove most of the material and then used a dremel router to finish the profile. When drilling, you have to be careful when breaking thru, I drill into a piece of wood and use very low rpm to help prevent it from grabbing. One other thing I learned the hard way about the stuff is that loctite destroys it, so you need to keep it away from lexan. It just causes all these little fractures and it just falls apart. It's very sad to see your finished part crumble in front of your eyes.
Ben, thanks for your input.
I was considering leaving them on all the time, the three should use 0.54A, which is not much. In fact at first, I was planning to see if I could get away without using the fans at all.
My Geo is(hopefully) going to be a low Amp draw(144v)/ watt per mile car, at least that is what I'm shooting for. That coupled with the fact I don't drive the freeway much and don't need to climb hills, should keep the controller temps down.
harleqiun2,
Thanks for the temp data. I may not have to use the fans at all.
When I went looking for heatsinks, the large ones were very pricey, and due to building my controller prior to getting my Geo, would not work for my planned installation.
That lead me to the CPU coolers($5.99 ea) that fit directly above the heat spreader and don't get in the way of my mounting brackets.
Thanks again,
Joe