Glad you got it done. However, I have changed several in both early and late 463's and all I ever did was take the bolt out of the pulley that you get at from outside the frame. With the bolt out, a new belt goes right in. 453's may require the engine to be loosened, but I absolutely know FOR SURE that on a 463 only that pulley bolt has to come out to give enough clearance to slip the belt in. Still, glad you got it. Next breakdown will be the centering springs on the steering if they haven't been changed already. Another common repair is the electric fuel shut-off solenoid. It works "backwards" of most others, as electric current holds it open. On most other diesels I have the electric current shuts them off. Glow plugs fail commonly as well. I can't remember if 463's have case drain filters or not--one of my guys does those maint items, but if they do, I'd certainly change the cartridge(s) inside them. Lots of "junk" inside means a problem is coming....