What is it for? Near the bellhousing area on the back driver's side of the block. Flat machined circle with a threaded hole. I noticed my '76 350 had one as well, but was not threaded. Engine in question is a '70 SP 350. I heard that it was for the clutch linkage in a 4 speed car, is this true? Was it only threaded if it was going to be in a 4 speed car? or did they thread them anyway? As mentioned, my '76 350 did not have the threads, but I imagine there were next to no Century's with 4/5 speeds so they omitted the threading. Any input is appreciated, always hungry for Buick knowledge.
