I have a DA50 in a Top Flite P-51 mustang. It didn't get as hot as yours but it did get quite warm. A fellow club member suggested getting more air going to the carb from the firewall so the motor would not be ingesting hot air which could contribute to leaner running. I opened up the airscoop under the wing and cut matching holes in the fuse to allow the fuse interior to become pressurized when flying... then I opened up the hole in the firewall behind the carb to 1.75" dia. This definetly helped. I don't know how to do this in an EXTRA.. but I'm passing the info along anyway