This Starter Has Unthreaded Mounting Holes. Units Vary in Appearance Between Old (Thinner, Longer Solenoid - 120-105A) and New (Shorter, Fatter Solenoid - 120-105 and 120-105B) Styles. There is Also a Marelli Unit, OEM No. 63221304 (102-216), Which Interchanges Here. The Same Looking Unit, But With Threaded Mounting Holes, is the 16408.