HOT Soak? Random Plug Fouling

Ok This one may be a little Tough, I had Just recently Built a 347 (9 miles 0n Engine, More Tuning time than Milage time) TrickFLow TW Heads, TF Cam, Speed Demon 750 Carb,Victor. JR Carb ,etc, etc....well after I start it Let it Run for maybe 10-15 Minutes Then Turn it off, and wait till the next day and start it again I've Lost a Cylinder (Fuel Fowled) just one and Always one Cylinder Right after I start it, this is Random to, No Certain Cylinder, I've Set the Idle The Idle Mixture set screws 1 turn out, timing is set to "ear" (Need new Timing Tab) after I've Removed and Cleaned the Fowled Plug it runs great!! Till the Next day I start it....Is this a HOT Soak..? If so what maybe Could be causing this...?

***Follow up, Problem Cured!!***

I Have Figured out the Random Plug Fouling, Wrong Heat Range of Spark Plugs, I forgot that I had installed "Temporary" Hotter than Normal Plugs Because they were outta the right ones, (It's been about 6 months since I've messed with the car) it's always the most obvious that get's us.