19s out of the question??? Nope... Just depends on who you ask...
Do a search for threads regarding 18 and 19 inch wheels on '97s. You'll find a lot of information about possible rear suspension failure and the Porsche re-design. There's also a discussion of the same topic on Rennlist.
235-35-19 front on 19x8s and 275-30-19 rear on 19x9.5s. No spacers...