I already own the '47 model in size 36. When I bought them I was a tad bigger and had to stretch them out quite a bit (you can see the initial fit pics somewhere in 2016 I think). Also the fly was pulling open. I haven't worn them in a while and thought it would be best to just get a bigger size and shrink them down, so shrink-to-fit and not stretch-to-fit.
Now after I bought the size 38, I took them out of the box just to find they fit quite well
But I still have to factor in that they are stretched out to the max and after a wash the situation will change. So the size 38 washed would probably fit right from the get go and maybe I will simply wash them hotter and more often to make them fit properly.
Maybe size 37 would be my ideal size but I'm not entirely sure Konaka-san offers that size. I hope I can take some pictures for comparison today.