I guess you could do a rewire on a V. I did, but not continuous. Just had SME install the vdH MCS-150M, a notch above the SME V stock wiring. IMO the benefits of using this wire outweigh the liability of adding another connection (headshell leads) if the connections are properly cleaned and treated. (You couldn't use the MCS-150M for direct wire because it's too fragile, as is most decent internal wire.)
As for the SME IV, it uses a coated-ribbon type internal conductor which is supposedly terrific w/ MC cartridges (more freedom of the bearing movement) so I wouldn't want to mess with that.
As for the SME IV, it uses a coated-ribbon type internal conductor which is supposedly terrific w/ MC cartridges (more freedom of the bearing movement) so I wouldn't want to mess with that.