I think you can replace the ST4000 control head with a ST6000 and a S1, that way you can still use your wind
, speed and depth
transducers and maybe upgrade to a linear drive
at a later point. I have a ST4000 wheel
drive myself and have upgraded to a mkII, but in my opinion it is just a plastic toy thing, good enough to go below to make some food
or coffee but not reliable for long ocean crossings.