Nice T. You need to have that shroud or it will most likely overheat. Install the Intrepid fans instead. They're cheap and they move shit loads of air, I'll never go back to the clutch fan. Still need a puke tank for the coolant though.
I just switched to corn last November, only put about 50 miles on before the driving season was done. I went from being able to run about 10 psi with a couple degrees of knock on real shitty 91, to 18 psi so far with no knock whatsoever. My chip is programmed for 21 psi and I'm pretty confident...
Did the bolts end up being metric or standard? I don't know how to spec the springs but those are shoulder bolts. Bolt Depot has a vast selection of fasteners in every grade and material you can think of, that is where I would check.