Thanks, Diana. I'm working with counties of 20-30K population so not working with PUMS.
I realized after posting that it is problematic using the BLS calculator since it requires that you enter a month as well as a year to adjust from and to.
I found this on the page about comparing 2015 5yr ACS to 2000 Census, under Income section:
The Census Bureau recommends using CPI-U-RS adjustment factors published annually by the Bureau of Labor Statistics (BLS) to adjust 1999 median, mean, and per capita income dollar amounts shown in Census 2000 Summary File 3 to 2015 dollars by multiplying the 1999 dollar amounts by the CPI-U-RS factor of 1.4229669.For CPI-U-RS inflation adjustment factors for other years see Updated CPI-U-RS, All items, 1978-2015 [PDF - <1.0 MB].
and there's similar guidance for other years.