Hi Michael, thanks for the compliment on the 20 Custom feature.
When deciphering model years there are typically two things to look at - and fortunately 1948/49 is pretty cut and dry. Notice that R-20-193 up until R-20-324, all of the 1948 boats are spec'd with a "48-17" model number. Then there is a short period of no shipments, then in 1949 Chris-Craft began just calling it a "20 Custom" and did away with model numbers. Your boat is definintly a 1949 model.
There is a pretty major typo in that article that somehow slipped through the cracks of editing. In the data section, notice the far righthand column labeled "Extra Equipment." This column of data should have been marked "Backordered." All of the extra equipment was noted in the "Notes" section.
1924 Hackercraft 33' Runabout Evangeline
1938 Gar Wood 22' Streamliner Empress
customer boats in the shop:
1941 Chris~Craft 19' Barrelback #48878
1942 Chris~Craft 19' Barrelback #48904
1947 Chris~Craft 25' Sportsman Sedan #075
1948 Chris~Craft 19' Racing Runabout #150