That is why I like this site so much. Here we get the actual data for the year model described in the post! That is so cool.
I heard from mgalvez that he actually has a 99 (it's in storage). So it looks like he may need a short shaft. I am curious whether or not all Futuras in 99 had the same speed tube location as mine or whether some have the newer speed tube placement on the tubes. Does this affect the recommended shaft length? I really don't know. Here is a copy of my response to Mike. I thought it would be good to share.
I'm glad you were able to get the right information. I am inserting two pictures of my outboard installation. You might want to note that my speed tubes are glued to the floor rather than the tubes (later boats had the wider set up). I don't know if that change influenced the recommended shaft length? What speed tube arrangement do you have?
My Nissan owners manual recommends that the anti ventilation plate be .4 - 1.2" below the bottom of the boat. It also recommends that the anti ventilation plate be below the waters surface when running at WOT. My anti ventilation plate actually rides in the depression created by the keel bump, but is not fully submerged (the edges are under water). The outboard is not sucking air into the cooling system so I'm not concerned. It is possible, with a bunch of weight forward at low speeds while turning, to get the prop to ventilate if I accelerate. But under normal operating conditions it is not a problem (including hole shots with a rider).
What sort of outboard are you looking for? Still going for a 25? Would you prefer a tiller or a remote control model? Power tilt? There are a lot of used outboards on Craigs List. I guess with the tight economy a lot of people are selling their toys. If you give me some specifics I will keep an eye out for you, but I highly recommend cruising the different coast cities CG listings. If you are looking for portability the smaller outboard is the way to go, but the Futura rocks with a bigger outboard. I have a 40 hp Nissan three cylinder with remote control and power trim. It is heavy!
I reglued my transom myself too. I'm glad it was solid so I didn't have to replace it! I also reglued some edges on the speed tube case, a section of the floor to tube seams and my front ring patch. The whole thing has held up for something like 4 years so far and it gets abused! I hope you have as much fun with your boat as I do and feel free to contact me if you have any other questions.