Here's what I do:
I use my block heater for a few hours in the morning before I start 'er up. This warms not only the engine, but also the manifold and the carbs.
Before I put the heater in, or if I don't have time, I just start it and wait. After about three or five minutes idling to warm the truck up, it starts running really rough. At that point, its iced up. So, I turn it off, wait about three or five minutes, with the hood closed. This let's the manifold, and carbs warm up just enough, that when its started again, away she goes!!
But, I live in the pacific northwest, (drive my truck every day) and here its super humid. We are often pretty dang close to the dew point here in the morning.
I'm sure others have different ways of dealing with it.
In fact, you can also leave the trouble light next to the carb for a while to warm it up.
