Delco Battery Topper Resto

[Ls6 Ragtop]

Danny,
The assembly line batteries did not come painted as you guessed and the service replacements were indeed painted. Assembly line batteries also had a different date code format from from the over the counter batteries for warranty purposes.
The R79W was very similar in appearance to the later R89W as the case was the same textured looking plastic. The R79 and R79S batteries were rubber cased exactly as in your reference photo. R89 and R89S batteries were also rubber.
All 69-70 sidemount style batteries used the 3/8X16 threaded positive connection and the 5/16X18 threaded negative connections.
71-Up sidemounts switched to 3/8 for both connections and a downsizing from 7/16 hex to 5/16 hex mounting hardware as used on 69-70 models.
Your battery topper looks great, you can also get a more correct R79W sticker for it if as Rick has noted your car was built before July of 70. I've only seen 1 buildsheet for an LS6 built in July and it did indeed have R89W in the battery box 49 as well as 71 coded battery cables.
Chris