In Calibre, I've set up the Metadata Plugboards in Preferences so the books are named Title [#] Series. They also appear within the Collections lists in correct numerical order on the 350 as well, not sure if the T3 will also do that.
For the 350 reader, under Add new plugboard, select "device_db" and "PRS-505" (those 2 might be different for your reader). My source template is the following, destination field "Title":
{title} {series_index:|[|]} {series}
You can of course change the sequence around to whatever you want between the title, series title and number within the series.
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