Been idleing my 216 quite a bit lately and I noticed last night that there was a very small amount of liquid collected at the base of the carb near the spacer but on the carb. It was in the area of being below where the fuel line connects so I assumed a fuel leak. It wasn't. It was water i.e. condensation.
I wiped it away and it didn't collect anymore as I continued to run & tune the engine.
I have the carb spacer and working manifold heat (brand new spring with 1/2 a turn of tension and free moveable flapper).
I think in my case it's a combination of high humidity area, cold fuel entering a cold carb & engine and possibly an over rich carb condition as I was useing the vaccum gauge method of adj the carb & timing and I ended up leaning the fuel/air mixture some. Pretty much all of the above mentioned causes.
In any case good thread as I would still be scratching my head wondering where the water droplets came from

Dave