+1 to the bushing, and to clear up a few things, a sch 40 BH uses a 42mm hole and a sch 80 BH uses a 48mm hole. The sch 80 is beefier on the overall dimensions and both use the same called size pipe, a 1" sch 40 is the same O.D. as a sch 80, but the I.D. is smaller on the sch 80 because of the thicker wall.