Are you saying you have a leak coming from a plug on the driver's side of the engine block? There is an oil galley plug just above the oil filter and if it's leaking just tighten it more.
after everything done to stop this I found that the oil plug on the top of the cylnder block on the drives side is the one.Can oil additives stop this as otherwise I will pull the mill and replace/rebuild. been a long time since I came across this leak in a 350 chev . friends have said its common. ?