I don't own any stock, or have any other interest in Humminbrd. This is jusy FYI. Don't know what fishfinder/depth instrument MacGregor puts on all their boats, but on my '98 26X there was a Humminbird 300TX. I wanted to upgrade but din't know what to do it with. Didn't want to rewire/transducer, etc. I asked my golfing buddy/local sport shop owner,and he told me Humminbird used a universal mount that most any Humminbird would fit. I had him order me the 2006 787C2. I didn't change the transducer,(they do offer a up-graded transducer, at extra cost)just added the GPS lead up through the pedistal to the same mount (I did have to remove the mount so I could feed the lead through the small hole). I left all the extra GPS wire in side the pedistal, I mounted the GPS antennae on a short piece of PVC pipe in the mast support pole hole. Used a 3/4" PVC threaded nipple into the antenna base to a 1/2" nipple for the 1/2" PVC, 3/4" PVC won't fit in the hole, just short enough not to get in the way of the Main Sheet. I can't believe how well it read the Delta water ways, and Islands, even the small tulle ones. List was about $699, most sources could probably get 50 bucks or more off as I did. I still like paper charts, but wanted to tell other Humminbird users how easy it was for a novice mechanic/electrican to make the change, and how well I think it works.