Reply to "Can you pull the zf box out while leaving the engine in ??"

If yours is a Type 1 ZF, then I don't know because the rear mounting arrangement is different. If it is a Type 2, then yes...but be careful.
You will have to jack up the back of the engine to tilt the ZF upwards in the back. This means, after removing the rear ZF mounting hardware, you will need to loosen the motor mounts, then jack up the back of the engine. The problem is, the most practical place to jack it is by placing a wood block on the farthest back end of the oil pan. If you have an aftermarket aluminum pan, then it should handle the pressure. If you have the stock stamped steel pan, then you run the real risk of compressing the pan into the crank. It does not take much distortion to hit the crank and you are lifting a lot of weight. If you bend the pan, then you will need to buy a new removable crossmember and another mount (think it is a brake linkage mount), cut yours out, and then remove the pan for repair or replacement. Another alternative is to tack weld a large nut to the bottom of the pan and use a slide hammer to pull the pan back out. The trouble with this approach is, you are probably introducing some burnt carbon slag to the inside of the pan where the welds are.
If you have access to two cherry pickers, you could probably lift the back of the engine with one, and remove the ZF with the other. You'll have to remove the rear deck to do this...but it's not a bad idea anyway. It will give you a chance to inspect the welds on the lid hinges for cracks and distortion. This is a common problem and should be looked at.
Good luck!
Mooso