perhaps a future 6 position blade, and combining of Series/parallel settings on existing Z3's might be considered possible? if it was you would certainly have the most comprehensive choice of sounds, keeping both the Neck/Bridge combination as well as the many sound combo's from the existing Z3 set up...
although first time users might find it to be too much, the tonal options /flexibility of Dingwall basses has always been a cornerstone of their appeal (amongst the fantastic build, innovation, amazing finishing, and overall quality...) .
Sheldon if you ever decide to try a retro fit, (risk of damage to finish?) I am a willing Experiment waiting to happen with my Z3, it would be a great test bass given the unique body wood combo of Swamp ash bass and Alder Treble side...