Hi reefriot 13,
7, 8, 9, and 10 get tossed into the neighbors' yard.
The wall fitting, and internal replace all of that. The Jet Bodies are the same (even though they don't look it).
Yes you will still have 1 through 6 in the spa, and it will look goofy without the grate, but not as goofy as cutting a plate to fit the rectangle hole, and then plumbing the jets. (and fixing the leak, and fixing the leak).
The Microssage assembly also in your pic is equally dated as to what you want to replace. If you go with the "Shell Plug", then consider a more modern jet assembly.