In the end I decided to make some steps in a friend's workshop that would in turn provide some protection for the bodywork. I have them almost done but when I went to plan the attachment points, a problem arose: the support points of the The ends that are in the car have through holes so you have to put screws and threads, but the central support are threaded holes and I can't know what thread and pitch it is, I have tried with metric 12 but the thread pitch is not Valid, metric 10 is small, can someone help me with this information. What type of screw is appropriate? Thank you
PS: I leave you a photo of the project
PS: I leave you a photo of the project