GradyB, A peek into a couple of Chevy Master books (1929-46 and 1929-53) shows the original oil connector to be GM# 838217 for 1937-39 engines. Below is a snapshot snagged form an NOS one being offered to give a visual on what it looked like out of the box. IIRC, the removal of the overflow tube/plugging of the port was often done to increase oil flow to the rocker shafts and rockers. If you are getting good oiling up there, it shouldn't be a problem IMO.
Others with more knowledge/experience will chime in soon I am sure.
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
