Hey Guys,
Yes, we ran the fan on top of the GTB Heatsink on a Losi Buggy with the Standard body. You can leave a little extra room depending on how you mount it. We just used the standard Cut Line on the bottom of the body. It can also be done with the B4, but the racer had his body mounted a bit lower then normal.
You can use a buttonhead screw to prevent the body from rubbing the fan as well.
The fan will have enough wire to move around the car as needed. We've put a fan in front of the ESC blowing back at it as well. For most 2wd applications the fan will not be as crucial.
Thanks
Charlie