I've done a couple of 24v conversions and the cross-members are all the same. You need to make sure you are using a pair of xr4x4 engine mounts (on the block) not the original 24v ones are they are for the rwd engine mounts.

The easiest way to do this is to bolt the diff onto the engine then lower the engine into the engine bay and raise the cross member into position and bolt it all up. You can fit the steering rack afterwards with all the bits in place.

If it's not going on easily, you must be using the wrong engine mounts.

Stuart