my experience tells me that if you make sure you get the seeds and the veins out, scraping with a spoon, then rinse them in cold water (you want to kind ofrub them down as you do like you're squeezeing them a bit), then add the cream cheese mixture, then slow coook them (on the smoker of course, but the oven will work, too) for a good long time at a low temperature, they will NOT be spicy-hot at all.
i do not know what in that procedure makes it so, it is possiilble that it is a combination of all. but my wife can NOT eat spicy foods, and these are acceptable to her when prepared as i say above.