I'm in an area of AZ that only has a Toyota dealer, so I've been
wary whether they know the actual maintenance schedule for
my '04 SC430.
I did some skunking around and found this Lexus.com source and schedule .pdf.
Not sure if it varies much for other model years,
but if you'd like to check here's the way to get a schedule
for your particular model years (have your vin number handy):
Go to lexus.com.
Click on Owners
Register your Sc430 using the Vehicle Identification Number found on your dashboard or door sill.
Once registered, click on "Service" from the drop down menu
Click on "View Maintenance Schedule
Then click on the .pdf link
This sign-up was quick and easy.
Reviewing my situation reveals that lots of these maintenance points have not been
performed per this schedule, but will be next time.