(Pete) Note that Saxophone.org and a couple other places advocate that the Radio Improved horns after 209xx should all be considered Jimmy Dorsey models.
I disagree with this, as an actual Jimmy Dorsey model had the left hand sheet metal keyguard and a few other differences.

I'm relatively sure that only altos and tenors were stamped "Radio Improved." I'm still going to include other pitches with the same s/n range here, just to be consistent.