Today I test fitted one IS300 wheel on the rear of my 98 ce v6 5spd. It had Goodyear Eagle 235/40/17 tires. Happy to report that there's no rubbing! there's about 3-4mm between the tire and the strut. I took a few pictures if anyone's interested, including pics of tire-strut clearance (both between tube/sidewall and spring perch/tread), as well as a few exterior shots. My web server is not working very well because my ISP is having issues, but I have the pics posted here:
http://www.gibson99.com/temp/is-wheels
these are just camera phone pics so they aren't super sharp, but they're good enough!
If I get these wheels, I'll get something taller than that to help fill the wheel well, because the 235/40/17 *looks* to be a smaller diameter than the 205/65/15 I had just taken off. a taller tire would also give me a little more ground clearance to help out with speed bumps.
maybe 235/45/17, since there's a Sumitomo on tire rack for like $68/tire right now.