You sir seem to be completely confused by terms
BLPs are just textures. Deleting anything from texture won't really help you much, as that will on any part of mesh without alpha blending mode produce only white areas, but it will not actually remove part of mesh. Which means that deleting equipment parts of texture will just make that equipment white, it won't remove it.
You need to convert M2 to M2i, open it in Blender with M2i plugin (Google.) and delete that stuff there. Thats all I can tell you, as I don't know process myself. If there are any issues with this process or with this particular model - yet again, I can't really help you any further.
