Hi fred I noticed you have a remote oil filter on your yanmar so maybe you can help.I was at the WM discount store yesterday and picked up a remote oil filter kit for my 2GM20 and the oil filter treads are hlf inch and so are the treads on the plate that goes on the motor but it won't go on.Any help before I try something else,I stop fooling around with hot rods a long time ago but I can see you still do with your camaro. nick