North American Aviation X-15A-2 -Texture space (part 3)

My next problem is I would like to use the existing texture file of the X-15 for the X-15A-2. However I have to add a extra section to the main fuselage. I don't want to re-create or make a new texture file, I just need to alter it.

Draft Texture file

It's a bit like a jigsaw, without the finished picture. I think, for now, I'll move the Wings over to the left and move the landing gear and small details over the the right. However I can take out the other Aircraft number out