OK, I want to convert my regular old speedo to gps speedo... what am I going to have to take out ( 0ther than the gauge itself) and where will the new GPS speedo get is sat signal from. I do have gps on the boat so does it have an auxiliary port for the gps speedo???

Dont forget to pinch off or plug the old speedo tube or you will get wet feet.

As for the signal, depending on your GPS, some have a output wire you can tap into, and provide signal to your speedo. Depends on the unit you have.

yea the tube will have to be taken care of...where does the tube start at the drive...that is where it makes the most sense to disconnect or plug it.

If it is a bravo boat the tube is part of the drive/drives. If you put the dirve on trailer tilt you will see where the tube comes out of the lower unit on the back side. Unhook it there, then plug the tube on the transom side.

thanks...couldn't see the damn thing when I had it on the trailer last time.