RE: Power Expander & Fasst RX Placement
I Had the same concerns as you as far as FASST, Smart-Fly PE Set-ups and the dreaded heat issue. This photo is my set-up in a 35% YAK 54. As you can see, the reciever is installed in the stock location. The biggest concern is not allowing the equipment to "Heat Soak" while sitting on the ground in the pit area prior to flight. As long as it is kept away from heat sources, ie; Mufflers, Headers, Tuned pipes, Voltage regulator Heat sinks, Not Wrapped and insulated in foam and above all....shaded from Direct Sunlight! You'll be Fine.(A White Towel over the canopy works great.) Most of my Flying is here in the Southeast and temps have been over 95 with NO Problems!
I've done as much reading about the subject as possible using this and other Forums, what I found is, 99% of the problem shows up when powering up after the airplane has sat in the pit area, the reciever "Red Lites" and won't Bind to the Transmitter.