Simon.
Luboil connections main engine.
Below is a crossection drawing of the main engine showing how the internal luboil system works. A luboilpipe on the outboard side, (not interfering with the crankcase doors) leads oil through drillings in the A frames (red) to the main bearings where it goes through drillings in the crankshaft to the crankpin bearings, then down in the crankcase bottom and drains via the lowest point fore and aft to the external drainsystem. Hopefully you are able to trace the external supplypipe along the engine, unfortunately I don`t have any picture showing same.
Tore