With all the stand-up equipment (station stuff, breaks maybe), it might just be easier to build a new ride. The ride also may be heartlined to be ridden standing up. That would be about as easy as making top gun a flying coaster, in other words: almost impossible.
Maybe with all this Titanic talk the park will actuallt thinm of nameing the gyper (if we ever get one) Titanic. Heck all the artwork, teasers & videos have already been made for them.