Good morning, firs of all sorry for mi english... I am from Argentina and I need your help. I receive a new pouland tractor with a B&S 17 hp ohv. The owner who give me the machine, mixed by error the push rods (they are different). I need to know two things: 1) wich valve is at the top and wich at the bottom 2) wich rods I have to install at top and wich at bottom? Thanks for your help...