For those wondering if a 2003 factory glass soft top and frame will work in a pre-2003 Boxster, it does. Today, my friend Maurice and I removed my old plastic windowed top from my 2001 Boxster, and bolted in a complete 2003 factory glass top and frame sourced from a wrecked Boxster. It is a direct plug and play bolt in. For pre-2000 cars, the top relay and top transmission microswitches that tell the top how to cycle are different, so there's a bit of extra work in order to make that work. For 2000, 2001, and 2002 model year cars, it is plug and play bolt right in and operate.
The advantage of swapping in an OEM vs. GAHH or other aftermarket version top is that the OEM version accomodates a larger glass window without sacrificing engine access from the top because of the 4th bow in the frame. The GAHH aftermarket tops have to stretch over the pre-2003 3-bow frames, and thus, the glass area has to be smaller, and there's extra pressure put on the glass as it folds.
Before...my 01 with the plastic window:
Getting ready to unbolt the old top and frame:
Marking the v-levers/push rod prior to disassembly so that we know exactly where to reconnect when putting in the new top:
Old top completely out:
New top in, and looking great:
Interior shot with full headliner and glass window:
Couple more:
And a video of the working 03 top on an 01 Boxster:
http://www.youtube.com/watch?v=hGCKcRrmR_c
Hope you enjoy the pics and video!