As promissed a while ago I place some pics of the instruction paper for the GM 43. I finally found it when I was looking for other stuff in my boxes.
This one is written in French and Dutch, I don't know why, maybe for the resistance, but I also have the German version somewhere, but in fact they are the same.
One thing I didn't know myself was that to modify it from a AP to a AT mine, they had to use a different detonator. It doesn't say what type, but it looks like a Zb 35.
Also you can read the blocks of HE were 200 grams, and you could fit in 5 blocks for the AT usage.
If I find the German version I will also post some pics.
If somebody is interested in a copy just let me know, as I know these instruction papers are very hard to find.