[mMad Dawg]

I have a 3/16 hole punch and flange tool . It works fine. However if you are concerned punch them 3/16 and ream them to no more than 1/4. Try the 3/16 first , if you put them a bit closer together thats all you need. just remember to clean both sides of the panel especially if you use a drill. Dont forget to spray on some weld through primer. Have fun Gord