I drilled out the 4 corner spots for holes...came with 4 bolts and only one hole LOL I get it, optional holes ;-)
Well the 4 holes matched up with the holes in the external waterproof box I used, for a generator cable end. Found another bolt and used 5 to hold it on very securely.
Exactly what I needed. How long will it last...well, there is one on the side of my 130 year old house...been there for many decades.