I have studied the manual and its clear that the "big ends" or conrod bearings are accessible when you remove the pressed oil pan. But can you access the main bearings? There is a comment about the lower aluminium casting supporting the mains so does this have to come off to access the mains and is it a pain in the ***.

 

Pistnbroke,
Our 4.0 V8 engines have a 'main bearing ladder' or sometimes called a 'Bedplate' or 'Bearing carrier'. This is the casting that the Manual is referring to. It has all of the five Crank main Bearing Caps joined together into one machined aluminium monoblock. This is one of the reasons the 4.0 liter is so strong. See pics.

I would not recommend considering removing the bearing ladder from the engine when it's still in the car - if it is even possible.. This is a major component and normally assembled with the engine upside down. There are many procedures to work through involving cleanliness, Sealing, oil seals and torque sequences etc.

Having said that, there may be members in this forum who can elaborate further or perhaps correct me!

 

I can see from your photos that its not possible as all the bearing caps are incorperated in one unit. this means changing the thrust bearings is not possible . Thanks