IMHO ----------it's a fantastic find and a fantastic car. 3 of these on the planet, out of 2,786 built. During the Cadillac Lookalike Years(1923-1924/25)... yes it's the 6, but about the same HP as the 8. Engine designed by Cadillac. Perhaps they envisioned getting into the Owner Driver niche that Pierce & Packard led, followed by Peerless, with a less ponderous lower luxury pricepoint [Packard "Single Six"/"Pierce Six-80", "Six-81"], but declined to add a 6.............and Peerless wound up with it.
As you know, Cadillac's President bought Peerless and brought over much of the firm's officers to run it in 1921, as well as the Collins Six engine. Richard Collins increased sales and got a bonus for every one of the 6-70 models *sold over-a-million-dollars-worth, but left in DEC 1923.
*over 14,000 Peerlesses w/ this engine sold 1924-1929 between 4 similar models