So I finally managed to round up an 04-05 shift knob (thanks Skafia). It does seem to make for a better shift feel, although I haven't been able to drive the car much since installing it. I take it my 03 shift boot is designed differently than the later cars. I now have a saggy shift bag with no obvious solution. I don't want to modify my existing boot and cause damage as it appears they may be discontinued. A new 04-05 boot is $400.00. I expect others on this forum have run into this issue before, and may have come up with a reasonable solution. Any advice would be appreciated.