I did not know there was 2 CB tank sizes, plus the smaller CL tank..
There's actually 3 different CL tanks, too. The 1968-69 2-tone type, the 1970-71 (my personal favorite) version and the last one 1972-73, which were sold longside the CB/CL360 twins (and sold better). I used to race my 1970 CL350 against the "new" CL360 guys, could whip them in stoplight contests by 3rd gear @10,000 RPM (tach went 10,500). The cams got tamer in the 1972 versions of the 350 twins, redlining at 9600 instead. Those bikes were bulletproof.