There's not much to say about this little diy plate except that you can make it in minutes.
Hot Rolled 1/2 steel - You can can get this at any bigbox or order it here
(.59c for 12")
Socket cap bolts - the ones shown here are from 8020 as they were left over, however you can use any 1/4-20 socket cap screws with a washer if required. These are 1/2", yet 5/8" lengths should work.
You only need to drill and tap two holes on 1.5" on center or what ever distance fits your application.