Was the Highlander it's own model with badging or an option package?
hey chief. my guess would be the latter.
Reading that Chrysler sales director's letter in March 1961 to the dealers announcing the deal, it talked about what the "package" was, the price, the point-of-sale materials to use IN the dealership, proforma ads for local print media, etc.,. suggests that was a typical seasonal promotion all domestic OE's were into.
what follows is all stuff you know .. just my humble opinion based on my experience.
Apparently, the whole car was "new" in 1961 when the "Newport" name plate/badging from the recent past
became its own model.
An "affordable, full size Chrysler" was "news" and a selling theme/hook for the Newp it seems to me.
The "hook" in those days, was to "get them into the showroom" and work your sales magic on them (for this low price, "entry" model, full size Chrysler, or maybe
upsell them into a NYer or 300 or something).
Since the model itself was "new" that year, the "hook" was a combination of taglines that conveyed emotion, and for this car "Highlander Hightime" with a tartan interior was the new Newp's extra contribution to the hook.
Something Buick and Ford and didnt have in their cars to make your friends "ooh and ahh" when you pulled up at church, or at the office, or at the club in your smartly-copped, full sized, '61 Newp. Powerful V8 with good fuel economy too!
To juice sales mid model year, unless the product choices were "cheap" to implement - e.g., unique paint colors, interior fabrics, option availability at lower price points, etc.,) - the factory/bean counters would tell the marketers to go fly a kite.
Tool up something new BEYOND the whole new Newp they just did that year, do all that engineering, etc, and you don't move any more IRON, was kiss of death to a sales career in a car company back then.
LSS, looks like a "package" to me, to help build showroom traffic for the new Newport, and I defer to smarter people to assess the car itself, but,
to me, only difference was the tartan fabric in this one vs. "regular" interiors/features available on all other Newps.