How difficult a job is it to replace a damaged oil pan on a 2003 Volvo S 40?

What is your question?

Today I learned my 2003 Volvo S 40, purchased used early last year, has a damaged oil pan that some clown repaired with liberal amounts of JB Weld! The damaged and rounded off oil drain plug is now non-removable--no oil changer in town will touch it. Is removing and replacing the oil pan a D.I.Y. job or should I just throw in the towel and take it into a shop? What is involved in the job? I have moderate to semi-advanced mechanical skills but do not want to get into a major tear down in my driveway. Thanks for any useful advice.

How long has your 2003 Volvo S40 had this problem?

It came with the car--purchased used.