Basically, Get the seat in a comfortable position for you.
You can mock it up using phone books, wood blocks, Whatever you need to do.
The full containment seat IS the way to go. Safety First!
I get that whoever you bought the car from was most likely taller than you.
Did you look at the diagram of how he set up his front bottom mount?
I run a different series than you do. My seat mount goes from frame rail to frame rail. Similar to the design posted. And YES, I think that this is the way to go. Seat mount needs to be welded between the frame rails.
On the rule about using a block (steel or aluminum) behind the seat... Think about it. I have seen people mount tubes that go directly into the back of the seat. Kind of mounting a spear behind your back. I would think this isn't your best bet from a safety point of view.
To get your seat to a correct layback angle, you may need to buy a different seat or adjust your mounts. As I have not seen your fit in the car, I can not tell you. What you describe tells me the angle of the seat will not work for you. "Staring at the sky" is not a good fit. If you are strapped in properly; Yes, it will be hard to reach the ignition switches. You can always relocate those if necessary. Or add extensions to the switches.
In similar train of thought; Build your seat mounts higher so you "can see".
Steve