End result.
The mechanic at Robson basically said not to waste my money on them checking the big end as they haven’t heard of one failing yet and they had a surprising number of GU's in there so I guess they work on few. Rear main seal and idler pulley assembly done, drive it home yesterday arvo and she is still running like a dream albeit without an oil leak.
Had a good chat to mate over the weekend who is diesel mechanic by trade and even he was very sceptical. He also explained to me how the big end works and what happens when one does go. Wait and see I suppose.
Bought some Roadside Assistance just in case but even if she does go its nothing I am going to stress over, if it happens it happens.