Dinga ling, mate from what the very knowledgeable people on the subject have told me on here, the later models have slightly v'd bottoms, are 3 inches wider and go slightly better, but with that being said still a great boat to go way outside. Good luck finding a trailer, I looked for months was about to start making one when I found one, after I brought it I had phone calls if I wanted to sell it, as I said, very hard to find.
Where are you located, if your pulling up the floor just to check the tanks, consider just pressure testing them, no more than 3 psi holding pressure, mine were 200lt stainless, I only pulled up part of the floor to check condition as the floor had been replaced by the previous owner, I needed to know what type of job he did before I started the rebuild.
Good luck, takes lots of time....Doug