Gps or paddle wheel speed control.

Hey guys, I just sold my boat. And won't be getting another any time soon. So I'm stuck behind my uncles 1987 sea ray. We built a ski pole for it which gets me by for now. But one thing I really want is speed control. I simply cannot afford to pay the $1000 for perfect pass especially since it isn't my boat. But if I could piece together a system. Or find one used that will work with a 4.3L v6. But I see peices going for decently cheap on ebay. I just don't know which all pieces I would need. I don't care whether is gps or paddlewheel if I can get it all for a good price. But if someone could inform me of which parts I would need for either setup that would be awesome!

Sorry for the long post. Thanks for any help!

You will find a few pieces cheap, then find some parts expensive/hard to come by - such as the throttle servo. You may end us spending a bunch of time only to save a few bucks at most.

You are better off trying to find someone selling a used complete system, but don't expect to find them giving that away either.

You can save a few bucks with this system:
http://www.hydrophase.com/

It didn't meet my needs but will likely meet yours.