Re: Glastron gt 150
I have a Glastron V156 with a 90. The GT has pretty much the same hull with a different deck. That's mine in the avatar
The Gt 150 will perform quite nicely with an 85 hp engine--for a while and for wakeboarding. You will in all probability need to buy a prop with 2 inches less pitch for boarding or skiing. If you have power trim, tuck the engine all the way in to pull out the boarder, then trim out. If no power trim, move the tilt pin 1 hole closer to the transom. With 85 It will be just slightly underpowered for slalom skiing and a good skier will be able to pull the stern out on hard cuts. He/she will actually be able to out-accelerate the boat and get ahead of it on these cuts. Wakeboarding speeds are slower though and loads on the boat are less. That combined with the area of the wakeboard makes getting up on the wakeboard and maneuvering OK. As you get more experienced though the boat will become marginal for you.
The real problem you will find is that there just isn't that much room inside the boat for 3 people, vests, wakeboard, rope, etc. It gets real small real fast.
As for a tower, anything is do-able if you want to badly enough, but on a boat that small, I don't think a tower is made that small--you would need to make your own--and I think it would be overkill.