Great thread - I've just been doing similar postulating for my SVT. I was considering a BAT intake - this is an open filter which has a second "inverted cone" in the end. It is run in place of the air box. This increases the flow - but it's all hot air ! You can add a "cold air" flow to the inner part of the filter, but unless the end of the intake is set up for a ram effect ( which wouldn't actually force air into the engine as it would instead reverse flow the other part of the filter )it won't do much as the air will take the easier route from the engine bay. My conclusion is as you stated - that the open filter kit might help on a dyno, but in real use it might even be a loss. ( OK so the intake noise would be cool but that's not my goal. ). I have to say - like most other stuff on the SVT - the engineers thought it through and gave us a good solution already - the cone filter is big ( off a V8 as you say ) -and it gets a nice flow of cool air from the inlet tube. So unless you are going to build a real "cold air" system with the filter up front -you're best off not doing anything. I will put in a K&N - I run them on my race car and they work great - but only if you keep them cleaned and oiled. They have to be sticky to work. I have seen the SVT air box up for sale occasionally - I'd suggest you SE folks pick one up.
