I saw a spal fan that I could hook up to the trail tech battery and hopefully the HD stator would be able to supply them and the lights if needed. I figured I would try it with out the fans to see how she runs. I know the tank dose nothing for cooling only to let it suck the coolant back in once it cools back down. I would have loved to have the WR but there wasn't any in my area that were used for sale so hopefully the YZ will handle the trails without to many over heating issues. I just have to remember when I'm stopped to shut her down.
Like you said don't let it idle and just try it stock first, you may find it's not a big a deal as it seems. I try to be very conscious of heat build up when I'm fighting up a hill or stopped waiting for a buddy etc and I found it to not be a big problem. Having said that I run the Evans stuff too and find it useful within reason.