HowAny one knows how to straighten/Re-Align a cracked axle/diff in the bush?

Frank, smee again. Yes, you can bend some steel components by heating or running a weld on the opposite side of the bend and letting it cool or quenching it. This may however cause crystalising of the metal and create a fatigue point. My advice is to not even try straightening the diff and get yourself to a wheel aligning place who can do the job properly. A diff that is out of plumb by only a millimetre can have drastic effects to the steering and tyre wear. It's just not worth the drama and risk.