I haven't tried dipping an aztec in break fluid yet, but I don't think it can be a problem with the plastic, because I have bathed entire car boddies in break fluid for several days and even weeks without the fluid marring the plastic of the kit.
However I do have my questions about the "cleaning" aspect of this action, since the break fluid didn't actually completely dissolve the paint on those boddies, it kind of broke the paint in small flakes that were easy to remove from the kit part, but when those flakes would get in the nozzle of an AB ???