Sorry to add another thing to the list of things to worry about with these boxsters. This is my opinion by what I see from the salvage side of the business. 1997-02 tiptronic base boxsters came with the small coolant tubes and no third radiator. 2003 and 2004 came with the same larger diameter that the S and 996 use. I can't keep 97-02 used transmissions on the shelves. Even crappy high mileage non-tested transmissions sell quickly. But on the flip side, I rarely have anyone asking for 2000-04 S and 03/04 base tiptronics. The S has the third radiator and that helps. I think the real difference is in the larger coolant tubes though as the 03/04 base and 99-04 996 manual does not come with a third radiator.
Another thing I see from the salvage side. Three chain motors have been dropping like flies since the beginning of the year. I could have sold ten of them if I had them. I'm not sure why they are failing but they're dying a horrible death from what I've seen. If your 3.2 dies, be prepared to spend a lot as those are hard to come by