How long would it take to change a shot catalytic converter and put in a new one for a 1998 blazer?

The cat. converter is usually welded into the exhaust pipe, so it will need to be cut out in order to remove it,you can weld it back on or you can use exhaust pipe clamps to hold it into place.How long would it take to change a shot catalytic converter and put in a new one for a 1998 blazer?Just do it already.How long would it take to change a shot catalytic converter and put in a new one for a 1998 blazer?maybe one day.