Hi Pascal,
Things are going pretty well, all things considered. However, I do miss life in Africa. There's so little of old Africa left, and I so feel the loss. How are things holding up in Tanzania? Which area(s) are you hunting in?
I generally do the modification on my belt grinder (one of those designed for knife makers). You do have to work very slowly, cooling the BH in water often. I keep a large bucket of water at hand, and I always rest one finger on the blade while I work. As soon as the blade feels warm, I dunk it in water and swirl it around, to cool it down. Then I dry the blade and resume grinding.
By hand, the rasp used for initial setting of the edge bevel (shown in the sharpening article) can be used to reduce the blade width and change the taper.
If you use a mechanized tool to remove the excess stock, do go very slow and keep the steel cool. It's easy to overheat the steel and change he taper.
Keep in touch. I'll soon be bush again, and out of contact for a while, but I'm really looking forward to seeing the results you get. I think there will be more good single-bevel BH choices available very shortly.
Ed
TGMM Family of the Bow