You have some great pics there. I think you better get ready to spend some money though lol. These things seem to love money. I have a zxi750 (two seater) and a Yamaha LX 760 (three seater). I am learning from your pics and information, I have learned quite a bit by playing with them, but unfortunately I don't have the answers to your questions. I will say that in my opinion, I would not try to change out big parts unless you have good info on the swap and know that it is well worth the price. I would suggest you fix this one up and if you want more power (and you will in time) then sell it and get a bigger motor. That's all I have for you now but keep posting pics and good luck. Oh and the pads for these things tend to be expensive. I bought a set of mats for the Yamaha, but on the Kawasaki I bought a work out mat form wall mart and cut it to fit then installed it with a silicon adhesive. If you use paint on the ski it chips easily compared to the gel stuff they come with. If you can spray that gel paint it's better. If you decide to get the mats they sell on ebay they suggest you put it on with contact cement, but the contact segment will not work on regular paint, it pulls it up and try to put it on dry either way on contact cement. The adhesive silicon seems to be working well on the workout cut out workout mat. It was 9 bucks so it's hard to beat that. Good luck and if I can help more I will. Oh btw use something very strong for that front like tiger hair and I would build it up on the inside if you can get to it. They tend to crack back in the same spots, they tend to take a beating. BTW you did really good by getting the ski for only $75 the parts on it should be worth well more than that. Oh and can you take a pic of where the shaft goes out of the ski? I think mine may have a leak there and I want to know what it looks like from the inside and out if you have it.