I've tried calling tech support, leaving messages, and also starting a thread on the forum on the RM web-site, but getting no help with this issue. I cannot find anywhere in the instructions to show how to wire the tiller drive to the course computer. This was very straight forward with my ST2000, but there is no description anywhere in the installation manual or anywhere that I can find online throught their documents files. The real kicker is that there are three connections on the back of the receptacle for the tiller drive, but only 2 inputs on the ACU-100. Can anyone shed some light on this matter? Like I said on the RM forum, a picture would be worth a thousand words.