RE: New Top Flite P-40 60 sized arf
Here are a couple pictures I have during the re-build / engine swap.
I went with the pitts style muffler in order to keep everything "in-cowl" As you can see the exhaust is just at the bottom of the cowl. I made an exit "ramp" that aids the exhaust exiting the cowl (after ground runs and the flight it stayed nice and clean on the bottom)
I also took the chance to mount the top cowl scoop with magnets. Under the scoop I place a nice access hole for adjusting the carb (works perfectly) Also you'll see I hid the fuel fill under there as well.