Section 7.H.14 of the rulebook addresses steering for streamliners - and while it does discuss handlebars and doesn't talk about steering wheels, I'd say you'd best ask the M/C committee for a strict ruling. Just 'cause it doesn't say no isn't good enough for my tastes.
Steering controls are mentioned in a few other sections of the M/C rules, and in each case it talks about handlebars, not a wheel. Again -- since a 'liner is a one-off I'd ask for input from the top of the pile of motorcycle inspectors and rulemakers. Check with Tom Evans or Van Butler. And don't forget the easiest way - go to the SCTA website (a link is on the home page of this site) and click on the request for rule interpretation (I forget the exact wording -- Dan Warner knows and posts it frequently). That's your best way of getting a request into the rulemakers.
Speaking of that link -- I'll ask here and also go directly to them - I wonder if SCTA would allow me to put the link to the rules on the front page of landracing.com. It might help generate a better conversation between seeker of knowledge and the rulemakers. Dan, or anyone else -- let me know what you think of the idea.
Oh, man, I just noticed that you've asked the question in the Bub's topic, and since that event runs on AMA rules (or FIM, if that's the record you're after) -- it probably would be best for you to ask AMA or FIM for what they'll allow. Sorry for the confusion. I won't erase what I've said -- my questions and comments still have merit in general.