[rhandwor]

Take the damaged drain plug into a parts store with experienced help. I've bought a tap at the hardware you need a thread gage to get orginal size.
I've also bought a self tapping oversize drain plug it depends on how bad they are stripped. I've also put on new oil pans. You have to determine how much metal you have and then solve the problem.
My 1997 Ford F-150 I cleaned up the threads with a tap I purchased at the hardware store. I then used a new drain plug.