I notice that our US friends are leaving it to the Brits on this topic.
They may step up now, as they know the SCTA rule book better than most in speed sport.
A diesel cycle engine is a permitted internal combustion engine and can be used in most of the racing categories, just not vintage.
If the provider of event fuel does not carry a diesel product, then the easy answer (or only answer) is to run your diesel engine in the appropriate 'fuel' class. Then all you have to do is exceed the speed for a fuel lakester. From the post earlier from Stan Back you will need to go 140 or 175 mph.
You cannot run FIA records at Speedweek (as they no longer operate with two way passes). You will have to join the Mike Cook 'Shootout' event for any such record bid, joining a limited number of entrants.
For testing, before you visit Bonneville, there are speed events in the UK - on Elvington and Pendine Sands - where you should be able to reach representative speeds. Look up UK Timing Association who work with Straightliners on the web.