I haven't looked at the DMV Vehicle Registration Manual in a long while, so not sure what exactly it says today, but when they original added this "dune buggy" exclusion back in 2014 it was my opinion that they had completely miss interpreted what we call a dune buggy. Regardless, you mention a dune buggy to a title clerk and your application will be denied.
Here is the 2015 thread on the subject, with a picture from the manual describing a dune buggy as a stripped down vehicle was their description of a dune buggy. Is this description still in the manual or have they rewritten this?
Texas "Dune Buggy" TitlingI would not be surprised to find many of our type of vehicles are titled today as the donor car, to avoid this dune buggy mis-description issue.