Well, now what? Blown 4.4i

[jhall]

I'll keep a long story short. 2000 x5 4.4, died one day while my wife was driving it. Took it to a shop where they called the engine "toast" due to overheat. I respectfully disagreed with the over heat and had it brought home. Before I even got a chance to tear into it I looked and found a broken upper timing cover. I'm planning for the worst here. I'll probably continue to dig more into it just for shits.

So my real question:

Locally to me there is a wrecked '00 740i that still runs. Would this be an option for an engine transplant? I ran a cross check on realoem on various engine numbers: crank, pistons, head and they are all the same between the two engines. However the engine block does not translate across. Is this correct? Sorry to be so blunt with my questions I'm just having a hard time finding answers.