Using 9/16-inch wrench, unscrew and take off two nuts (1) and washers (2).
Take off U-bolt (3) and bracket (4).
Bypass valve (5) maybe stuck to exhaust pipe (6).
If needed, use hammer and chisel to pry up ends of
Using rubber mallet, tap off bypass valve (5).
Take off and throw away gasket (7).
IF WORKING ON TRUCK M50A1 OR M50A2, GO TO FRAME 8.
IF WORKING ON TRUCK M50A3, GO TO FRAME 9