Great to know there is another Vision 36 owner out there!
You've probably already found it; yes there is a conduit - I access mine on the hard though after haulout each winter - the conduit stops around 2 ft from the base and I've fed a snake up it and been able to get at it through the halyard sheaves at the top of the mast. Not sure how close to the top the conduit ends.
If there is already some other cable (masthead light?) in there you could use it as a runner, pull it through with a feeder string then pull back 2? Probably worth replacing any cable that's been in there that long too (I did all mine).
