Nissan Repair: Nissan Serena - engine removal, nissan serena, prop shaft

Question
Hi.  We cooked the engine and are intending to replace it with a 2nd hand engine.  We have jacked up the vehicle securely.  
Does the engine come out with the gearbox? It seems, to us, that the best way will be to lower them both down to the garage floor, and then slide them forward, to get them both out as one unit. Can the starter-motor wiring be removed without removing the air-intake manifold?  Should the exhaust system be disconnected at the exhaust manifold?  Do we disconnect the prop-shaft at the diff and then pull it off the gearbox?
There is a click-click from the right rear region that sounds like a bearing when turning to the right.  Are there any special precautions necessary when changing this bearing?
Do you know of a site  that has diagrams?  
At the moment we are simply disconnecting all the wiring and pipes we can see that connect directly to the engine.

Many thanks, from New Zealand.

Answer
Jeremy

I would pull the engine separate from the transmission and take it out the top.  

If you have the tools to pull the engine from the bottom it is best.  You can simply support the sub-frame and disconnect the wiring, hoses, exhaust, and drop the unit as an assembly.  Make sure you have the back supported since the weight coming off the front end sometimes causes the empty front to tip up when the sub-frame is removed.  I do not have manuals for your car but there are many links out there to parts and support.  Check out those below.

http://www.oldclassiccar.co.uk/modernads/nissan_serena_mpv.htm

http://en.wikipedia.org/wiki/Nissan_QR_engine

http://www.nissanlargoownersclub.co.uk/

http://www.nissanforumsph.com/forum/