I am just a few years off completing a 5" SPEEDY loco and looking at the chassis, it occurs to me that it would be near impossible to get oil into things like eccentrics for the water pump and lubricator. I have added a "lube" system for the axle boxes, but that wouldn't work for an eccentric as its path would move away from the delivery point as the axle rotated.
Even if you had a jig to turn the engine upside down, the oil holes for the eccentrics would be unreachable.
What does everyone else do ?