What If Build Ideas...for Land Speed Racing

So, what if...

You decided to go to Bonneville (Speed Week this week has me thinking). You guess you need 700-800hp to get your 68-70 B Body close to 200mph. You need to run WOT for about 5 miles a several times for licensing. What would you build for a motor? The cars are heavy typically by design for stability. It would seem less grueling than the Silver State Classic Challenge being this race is 93 miles of near WOT.

I saw a video where Pete Turk sprayed nitrous for a full 70 seconds!! I assume a very good rotating assembly, what would you use? Max wedge sized head ports?

Big Block N/A?
Big Block with boost?
Small Block for lots of RPM?
Cross bolted mains style block?
E85? Methanol?

Edit: Keeping a reasonable budget for an average poor guy.