For the sake of possibly gathering a tiny bit more data - and because they were really cheap - I bought these two ads, cut from magazines, on eBay. Both measure about 6 x 5 in.
This one is dated, by hand, November 10, 1947.
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This one is dated, by hand, March 15, 1948.
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I'm not going to fuss over tiny details here - I have done that enough already - I'm mostly just posting because I paid for them, so why not put them out there where everyone can benefit.
The thing that catches my attention most is the seat in the first ad. I am really not sure what to make of it.
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One note: I have not seen, to my knowledge, a Luxury Liner with original grips that are similar or identical to the ones shown here.