I am having a little trouble understanding the NEC book on panel placement. 408.13 does not give any straight forward messurements and 408.8 gives it for switchboards. Exhibit 110.18 and 110.19 is the closest that I found to an exact placement. Article 230.70 tells me where I can't place it , and there is nothing that states if I need a plywood backer or not and if so how big it must be. All I want to do is put in a 100 AMP Subpanel . Can someone help me out of this bad dream I am having .
Thanks for your time.