I think I solved the riddle on the air cleaners. The first NAPA counter guy I spoke with on the phone typed in 2083 and came up empty (Gold filter not in stock). The second guy I saw later (when I went to the store to have them order the 2083s for me) typed in 22083, which turns out is the Silver version (cheaper, but had two on the shelf). Yes, they were on the shelf and also only $7. They look fine to me, and certainly better than the dirty ones I had on the car. Good enough for me, especially since I won't be driving in any dust storms or tens of thousands of miles per year. The NAPA web site says they are made by Wix filters for NAPA. They fit well and will do fine, even if they may have to be changed a bit more often than the gold version.
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