Yeah congrats!
I think hoosier is right, ferment with 1056 at lower temps on this one. The way i see it, the bigger the beer, the more yeast stress, the more fusels and other issues created. Lower fermentation temps help suppress those and get a cleaner more drinkable "big beer". I fold a hand towel and attach it with a bungee to the side of my fermenter; the temp controller probe goes in there. According to jamil, it will read within 1F of the temp of the wort in the center of your carboy/bucket/conical. So if you attach the probe that way, just set your controller to the desired fermentation temp (60F if you go with hoosier's sage advice).
Your malt bill looks great! Its a balancing act for sure...balancing malt selection, grist composition, mash temp...to yield the body and mouthfeel you desire. Ive seen partial mash recipes where half the sugars come from dme and the mash temp is 158 to help lend body. Some here mash at 148F, which is on the low end for sure. However, with the right specialty grains, like oats or flaked barley to add body, a lower mash temp (~150F?) sounds reasonable. Remember too if you treat it right, that chico yeast will tear through this beer.
All in all, it looks like youve done your homework. Let us know how it turns out and maybe we'll have to brew it too!
Cheers, and congrats again!!!
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