Whatever method you use to patch the holes will require removing the pan for a permanent fix. You don't want oil seeping through the holes while you're applying the JB Weld.
If the inside of the pan isn't completely rusted with more pin holes about to pop through, the JB Weld method will work.
My brother used regular JB Weld to seal a sheared off engine cover on a motorcycle. Over 15 years and not a drop of oil lost.
