Can anyone give me a run down on how to set the timing on a 350 using a vacuum gauge.. I'm having a difficult time finding the right 6 3/4 harmonic balancer for the engine. It’s a GM 290 hp crate. It runs great but the timing mark is off about an inch... I have the bolt on timing tab for a 6 3/4 balancer supplied with the engine. It’s at the 2:00 position. They recommend using an 8" balancer but I have clearance issues with my power steering pump. Once again the engine is running great I just want to make sure the timing is set correctly.