Just a few comment as I was looking for something similar before eventually installing a below deck unit:
- in the past the wheelpilot consisted of a drive unit (the wheeldrive) and a control unit that included all the "brains". Ah, the rudder position as well but this is an additional feature let's say and you can have it with any wheeldrive, both new and old. Nowadays, a wheelpilot consists again of the drive unit, a new control unit (ST6002) that doesn't have brains any longer and a course computer (SPX5).
- whatever wheeldrive unit you currently have (black raython or the S1 grey unit) you can simply change that if your problem lies there (I mean with the drive rather than the electronics). Both are supposed to do the same job but I think the grey unit is a bit more robust than the old black unit.
- if you update to a completely new SPX5 you will of course need to change the control unit. Keep your old drive unit as a back up as you could still use it with the new unit.
PS: What is a "smart heading gyro 2 unit" that you have anyway? Is it a course computer or the new style control units? Are you sure it's a seatalk problem that you have and not trying to connect a new control unit directly with the drive unit?
