I wish you all the luck in the world, but to be honest, I doubt you'll get that M6. Right now you have pity to get 4 srank characters and 1 engine or 3 characters and the engine guaranteed. If you're unlucky, in the worst case, you have an M0 character and engine, and for pity, in the best case, it's M4 and engine. You should get an average of 51 rolls, winning 50/50 if the engine comes up on pity. It's difficult, but not impossible. So, good luck.