Previous owner took my 1999 4runner to those quick oil change places and must have removed the skid plates and put them back with half the bolts missing. The ones still there are stripped (discovered when I changed oil) so I want to replace them. They are Metric 8 mm, but neither course not fine threaded bolt screws in OK. i could try thread chasing the holes, but what thread, course or fine? I'm hoping someone else has been through this and knows something.